  In this article, by means of considering an isospectral operator equation
which corresponds to the Volterra lattice, and constructing opportune time
evolution problems with negative powers of spectral parameter, and using
discrete zero curvature representation, negative Volterra flows are proposed.
We also propose the mixed Volterra flows, which come from positive and negative
volterra flows. From the Lax representation, we demonstrate the existence of
infinitely many conservation laws for the two flows and give the corresponding
conserved densities and the associated fluxes formulaically. Thus their
integrability is further confirmed.
