  The supersymmetric technique is applied to computing the average spectral
density near zero energy in the large-N limit of the random-matrix ensembles
with zero eigenvalues: B, DIII-odd, and the chiral ensembles (classes AIII,
BDI, and CII). The supersymmetric calculations reproduce the existing results
obtained by other methods. The effect of zero eigenvalues may be interpreted as
reducing the symmetry of the zero-energy supersymmetric action by breaking a
certain abelian symmetry.
