  On the basis of hydrodynamic model of evolution of heavy ion collision we
consider emission of $\pi,K,\eta,\rho,\omega,K^*$ mesons directly from the
surface of quark-gluon plasma, with accounting of their absorption by
surrounding plasma hadronic gas. We evaluate upper and lower limits on yields
of these direct mesons in Pb+Pb collision at 158 AGeV (SpS) and 3150+3150 AGeV
(LHC), and find, that even in the case of the lowest yield, direct $\eta$ and
heavier mesons dominate at LHC energy at soft $p_t$ ($p_t\le 0.5 GeV/c$). This
enhancement of the low $p_t$ meson production can be considered as a
quark-gluon plasma signature.
