Conclusions
AGV in the present study area suffers from human activities as over
grazing and collection of plants for medicinal purposes. This may lead
to habitat degradation and vegetation destruction in some part of the
area. Knowledge of the SSB and its temporal and spatial variation is a
useful tool for conservation and restoration efforts. This study showed
that shrubs played an important role in restoring of herbaceous seeds
under their canopies. However, the extent to which shrubs affects SSB
characteristics is dependent on the species of shrub and the type of SSB
characteristics. These different roles of shrubs on SSB are advised to
be considered in restoration of areas through conservation of native
shrubs in the semiarid regions. Highest SSB density under the canopy ofA. scoparia with its potential in medical and grazing uses
increase the priority of using for degraded site restoration by this
shrub species. In addition, although E. stellata has a low or
intermediate palatability for grazers, it can be of priority for
rangeland improvement if plant diversity conservation is of priority for
the manager.