No abstract

I n January, millions of fish died in Australia's Murray-Darling Basin as the region experienced some of its driest and hottest weather on record. The heat also caused severe water shortages for people living there. Such harsh conditions will become more common as the world warms. Iconic and valuable species such as the Murray cod (Maccullochella peelii peelii)-Australia's largest freshwater fish-could vanish, threatening biodiversity and livelihoods. Rivers around the world are struggling to cope with changing weather patterns. In Germany and Switzerland, a heatwave last year killed thousands of fish and blocked shipping on the River Rhine. California is emerging from a six-year drought 1 that restricted water supplies and devastated trees, fish and other aquatic life. Across

Climate change will increase water stress in many regions placing greater pressures on rivers to meet human and ecological water needs. Managing rivers experiencing water stress requires a fundamental understanding of how ecosystem processes and functions respond to natural and anthropogenic drivers of flow variability and change. The field of environmental flows meets this need by defining “flow-ecology” relationships—mathematical models linking ecological characteristics and dynamics to the underlying flow regime. However, because these relationships are most often based on historical hydrologic regimes, they implicitly assume climatic stationarity. A fundamental challenge in the Anthropocene is how to model flow-ecology relationships such that the effects of nonstationarity can be captured. In the present article, we introduce a novel approach that addresses these shortcomings and show its utility through a series of conceptual and empirical examples. The framework incorporates ecological dynamics and uncertain future hydrologic conditions, as well as nonstationarity itself, thereby providing a viable framework for modeling flow-ecology responses to inform water management in a rapidly changing climate.

No abstract

No abstract