expression manipulation – How to drop/extract elements of a list which starts with Plus

I have the following list :

list={a^2, b^2, a^-1, a^2+b^2, (a+b+c)^-1, (a+b-c)^-2}

I want to break this list into two lists: one containing elements starting with Power and another starting with Plus. In this case it will be

list1 = {a^2, b^2, a^-1, (a+b+c)^-1, (a+b-c)^-2}
list2 = {a^2+b^2}

A priori the position of elements starting with Power or Plus is not fixed and also the elements could be complicated. Is it possible to do this?