  We describe the construction of a conserved reaction-diffusion system that
exhibits self-organized critical (avalanche-like) behavior under the action of
a slow addition of particles. The model provides an illustration of the general
mechanism to generate self-organized criticality in conserving systems.
Extensive simulations in d=2 and 3 reveal critical exponents compatible with
the universality class of the stochastic Manna sandpile model.
