Data from: Surface-water dynamics and land use influence landscape connectivity across a major dryland region

Landscape connectivity is important for the long-term persistence of
species inhabiting dryland freshwater ecosystems, with spatiotemporal
surface-water dynamics (e.g., flooding) maintaining connectivity by both
creating temporary habitats and providing transient opportunities for
dispersal. Improving our understanding of how landscape connectivity
varies with respect to surface-water dynamics and land use is an important
step to maintaining biodiversity in dynamic dryland environments. Using a
newly available validated Landsat TM and ETM+ surface-water time series,
we modelled landscape connectivity between dynamic surface-water habitats
within Australia's 1 million km2 semi-arid Murray Darling Basin
across a 25-year period (1987 to 2011). We identified key habitats that
serve as well-connected ‘hubs’, or ‘stepping-stones’ that allow
long-distance movements through surface-water habitat networks. We
compared distributions of these habitats for short- and long-distance
dispersal species during dry, average and wet seasons, and across land-use
types. The distribution of stepping-stones and hubs varied both spatially
and temporally, with temporal changes driven by drought and flooding
dynamics. Conservation areas and natural environments contained higher
than expected proportions of both stepping-stones and hubs throughout the
time series; however, highly modified agricultural landscapes increased in
importance during wet seasons. Irrigated landscapes contained particularly
high proportions of well-connected hubs for long-distance dispersers, but
remained relatively disconnected for less vagile organisms. The habitats
identified by our study may serve as ideal high-priority targets for
land-use specific management aimed at maintaining or improving dispersal
between surface-water habitats, potentially providing benefits to
biodiversity beyond the immediate site scale. Our results also highlight
the importance of accounting for the influence of spatial and temporal
surface-water dynamics when studying landscape connectivity within highly
variable dryland environments.