  A unitary orthosymplectic quantum supergroup is introduced. Two covariant
differential calculi on the quantum superspace $SP_q^{1|2}$ are presented. The
$h$-deformed symplectic superspaces via a contraction of the $q$-deformed
symplectic superspaces are obtained. A new $h$-deformation of the Heisenberg
superalgebra is given.
