Collaborative Research: RUI: The Pulse-Shunt Concept: A Conceptual Framework for Quantifying and Forecasting Watershed DOM Fluxes and Transformations at the MacroSystem Scale

Yale University, New Haven CT

Investigators

Abstract

The transfers of carbon, nutrients and pollutants from the land to streams and their changes as they move through river networks are issues that motivate environmental scientists and water resource managers. Dissolved organic matter (DOM) is a central chemical in streams and rivers that affects the forms and movements of contaminants, light penetration through the water, metabolism of life in the streams, pH, and the efficiency of water treatments by municipalities. This study aims to improve predictions of DOM formation and movement from small headwater streams and our understanding of the factors that change the amount and forms of DOM during as it moves downstream. One goal of this research is to greatly improve a computer model of DOM transport and transformation as it moves through a watershed and into the headwater streams. This model links rainfall and runoff that generate streamflow to the biological and chemical processes that lead to changes in the amount and forms of DOM. The model will be tested against actual measurements of DOM made in several headwater streams of the Connecticut River along its length. Measurements will then also be made in larger parts of the Connecticut River downriver that will help explain how DOM changes along the entire drainage network. This project challenges a long standing picture of how streams and rivers work, called the River Continuum Concept, proposing that a newer view may be required, referred to as the Pulse-Shunt Concept. This project will involve graduate students and a post-doctoral associate in the laboratory, field, and modeling ends of the research. It will also build on a partnership with the Connecticut Science Museum to construct educational activities and displays related to watershed ecology and management for the general public.