Dams, diversion of water, invasive species, overharvesting and pollution are degrading rivers and wetlands. Climate change may exacerbate impacts of these threats through predicted reductions in rainfall and increased temperature, decreasing flow and altering timing and variability of flow regimes. Papers in this special issue identify conservation-management strategies for wetlands and rivers through recovery of flow regimes, alteration of dam operations, protected-area management and improved governance and adaptive management. On most regulated rivers, flow regimes should be recovered by increasing environmental flows. Alteration of dam operations can also improve river health through structures on dams (e.g. fishways, multi-level offtakes), reinstating floodplains and improving flow delivery. Further, time-limited licensing for dams and accompanying regular assessments of safety and of environmental and socioeconomic impacts could improve operations. Protected areas remain the core strategy for conservation, with recent improvements in their identification and management, supported by analytical tools that integrate across large spatial and temporal scales. Finally, effective conservation requires good governance and rigorous adaptive management. Conservation management of rivers and wetlands can be significantly improved by adopting these strategies although considerable challenges remain, given increasing human pressures on freshwater resources, compounded by the impacts of climate change.
Optimizing environmental flows for multiple reaches affected by a multipurpose reservoir system in Taiwan: Restoring natural flow regimes at multiple temporal scales
