FlowPer: Indicator of Watershed Quality

In the analysis of watershed functions, we deal with complex factors that influence processes and patterns in the landscape that ultimately translate a temporal pattern of rainfall into a temporal pattern of stream flow, which aggregates up to a river. Downstream stakeholders start from what they want to see (”perfectly regular flow of clean water”) and observe a pattern of stream and river flow that doesn’t match their expectations. They search for interventions in the “anthropogenic” groups of causes (deforestation, land degradation), but need to understand the potential reach of such interventions, given the geological and climatic background. In the absence of knowledge of what happens upstream, an observer of river flow can deduce a fair amount of information from a time series of river flow data. The FlowPer model is focused on that. It can serve two functions: 1) summarize the key parameters that downstream stakeholders can observe on the flow pattern, for example, as a basis for conditional rewards for providing environmental services; and 2) serve as a parsimonious (parameter-sparse) “null model” that allows quantification of the increments in model prediction that is achieved with spatially explicit models (with parameterization first rather than parameter tuning to the data).