The chemistry of drainage basins: The Pulse-Shunt Concept
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.
Watersheds Rules of Life
Part of the NSF "Understanding the Rules of Life" Big Ideas initiative.
Microbial diversity and organic matter in major rivers
Greenhouse gas evasion from streams and rivers
Inland waters cover a small area of the planet and thus their impact on global budgets has received limited systematic study. Nevertheless, idiosyncratic approaches, have, in recent years, suggested that inland waters are key "hot spots" that control the processing of carbon at the global scale. The study of the roles of both the ocean and the terrestrial biosphere have made stunning achievements by launching systematic large regional- to- global networks. In contrast, the study of inland waters has lagged, largely due to lack of any centralized coordination and synthesis.