  We use the two-step density-matrix renormalization group method to study the
effects of frustration in Heisenberg models for $S=1/2$ to S=4 in a
two-dimensional anisotropic lattice. We find that as in $S=1/2$ studied
previously, the system is made of nearly disconnected chains at the maximally
frustrated point, $J_d/J_{\perp}=0.5$, i.e., the transverse spin-spin
correlations decay exponentially. This leads to the following consequences: (i)
all half-integer spins systems are gapless, behaving like a sliding Luttinger
liquid as in $S=1/2$; (ii) for integer spins, there is an intermediate
disordered phase with a spin gap, with the width of the disordered state is
roughly proportional to the 1D Haldane gap.
