  We study the additivity of various geometric invariants involved in
Reimann-Roch type formulas and defined via the trace map. To do so in a general
context we prove that given any Grothendieck category A, the derived category
D(A) has a compatible triangulation in the sense of [May, J.P. :The Additivity
of Traces in Triangulated Categories, Advances in Mathematics 163, (2001),
34-73], but not resorting to model categories. The result is proved just using
the structural properties inherent to D(A). In the second part of the paper we
apply compatibility to prove additivity of traces firstly and then additivity
of the Chern character, interpreting this result in terms of a group
homomorphism which plays the same role as the Chern character in intersection
theory with the i-th Chow group replaced by the i-th Hodge cohomology group.
