Abstract. The system size dependence for multiparticle processes has been recognized in both cosmic ray ("Stratosphere" collaboration) and at accelerator ("EMU" collaboration) experiments. The strong enhancement in multiplicity fluctuations for the most central light-light -(C, O, Ne) + (C/N/O) -collisions has been revealed at JINR-AGS-SPS energies. The sharp difference of light nuclear interactions are interpreted as the sign of intrinsic alpha-clustering in light nuclei.