Reclamation usually involves modification of the local environment to achieve some biotic target, but if the influence of
Landscape Condition on that target is great, we may fail to meet it despite efforts at the local-level. We sought to determine
the relative influence of local- and landscape-level habitat on aquatic plant diversity in shallow open-water wetlands. Furthermore,
we asked whether the influence of Landscape Condition should be attributed to direct (dispersal-related) effects, or to the
indirect effect of landscape variables that influence local habitat quality. Finally, we asked if spatial scale (300–2000m)
would affect conclusions about the relative influence of local- and landscape-level effects. Using structural equation modeling,
we found that Local Condition is consistently more influential than Landscape Condition. As landscape size increases, the
relative importance of Landscape Condition declines and there is a trade-off between its direct and indirect components. At
≤500m direct landscape effects were of greater importance than indirect effects, whereas indirect effects of Landscape Condition
became more important at ≥1500m. This suggests that the dominant mechanism by which land use influences diversity depends
on the spatial extent of the landscape. We recommend that reclamation designs include a high proportion of wetland habitat
and incorporate seeding/planting if diverse plant communities are desired. Additionally, we note that the influence of the
landscape is strongest within 300m. Thus, the focus of reclamation efforts should remain at the in-lake level and the immediate
surroundings: this is where efforts will achieve the greatest effect on aquatic plant diversity.
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