ABSTRACT:

Flow-ecology relationships are critical for developing and adaptively managing environmental flows. However, uncertainty often arises from data limitations and an incomplete understanding of the spatial and temporal attributes inherent to each relationship. Accounting for sources of uncertainty is critical given mounting interest to implement environmental flows at large scales, often with limited information. We used the South Fork Eel River watershed in northern California, USA, as a case study to quantify data gaps and uncertainty in flow-ecology relationships. Through a rigorous literature review, we found that few flow-ecology relationships related explicitly to the flow regime and none completely spanned the hydrologic or geomorphic variability exhibited across the watershed. Identified data gaps informed several sensitivity analyses within a Bayesian Network model which showed that the modeled ecological outcome differs by up to 50% depending on the type and magnitude of uncertainty. This study presents a general framework for quantifying spatial and temporal data gaps that can be applied to other regions and information types to improve the understanding of flow-ecology attributes and representation of uncertainty.

ABSTRACT:

Availability of water for irrigated crops is driven by climate and policy, as moderated by public priorities and opinions. We explore how climate and water policy interact to influence water availability for cannabis (Cannabis sativa), a newly regulated crop in California, as well as how public discourse frames these interactions. Grower access to surface water covaries with precipitation frequency and oscillates consistently in an energetic 11–17 year wet-dry cycle. Assessing contemporary cannabis water policies against historic streamflow data showed that legal surface water access was most reliable for cannabis growers with small water rights (<600 m3) and limited during relatively dry years. Climate variability either facilitates or limits water access in cycles of 10–15 years—rendering cultivators with larger water rights vulnerable to periods of drought. How-ever, news media coverage excludes growers’ perspectives and rarely mentions climate and weather, while public debate over growers’ irrigation water use presumes illegal diversion. This complicates efforts to improve growers’ legal water access, which are further challenged by climate. To promote a socially, politically, and environmentally viable cannabis industry, water policy should better represent growers’ voices and explicitly address stakeholder controversies as it adapts to this new and legal agricultural water user.