Geomorphologic, Hydrologic, And Biogeochemical Interactions In Stream-Lake Ecosystems Of The Sawtooth Mountains, Idaho, USA

EPA Grant Number: F5E11042
Title: Geomorphologic, Hydrologic, And Biogeochemical Interactions In Stream-Lake Ecosystems Of The Sawtooth Mountains, Idaho, USA
Investigators: Arp, Christopher D.
Institution: Utah State University
EPA Project Officer: Lee, Sonja
Project Period: August 5, 2005 through August 6, 2005
Project Amount: $111,344
RFA: STAR Graduate Fellowships (2005) RFA Text |  Recipients Lists
Research Category: Academic Fellowships


The focus of my research is integrating geomorphology, hydrology, and biogeochemistry in stream ecosystems, specifically in mountain streams in watersheds with lakes. I am primarily interested in how lakes change or disrupt downstream continua of river systems and affect sediment transport, flood regimes, groundwater-surfacewater exchange, and nutrient uptake and retention, particularly nitrogen and phosphorous. My broad hypothesis is that these physical, chemical, and biological processes are closely related and we can best understand them in abrupt hydrogeomorphic settings, such as where a stream enters and leaves a lake. This landscape setting also has implications for better understanding how river regulation from dams impact stream processes and what we might expect to occur in regulated rivers over long time periods.

The objective of this research is to develop conceptual models of how stream geomorphology, hydrology, and nutrient cycling operate in temperate mountain ecosystems were lakes are prevalent, and to use these ideas along with empirical data and mechanistic relationships to predict the impact lakes have on headwater drainage networks and connected ecosystems.


This research is primarily based on field studies, intensively at one watershed with a small lake, and extensively in approximately 30 stream reaches in 10 watersheds through out the Sawtooth Mountains, Idaho. I use geomorphic surveys and mapping, hydrologic monitoring, conservative and reactive tracer injections, and biological and water quality measurements to characterize the structure and functions of these sites over a 3-yr period. These data are then compared graphically and statistically among sites and seasons, and used in empirical and mechanistic numerical models to describe and predict how stream-lake ecosystems function.

Expected Results:

The broad applied focus of this work is to provide a more detailed understanding of nutrient transport and retention in pristine (reference) mountain watersheds according to physical landscape attributes that can in predictive modeling, such as spatially explicit models of drainage networks. I expect to publish 1 paper on geomorphology, 2 papers on hydrology, 1-2 papers on biogeochemistry, and an integrated paper on conceptual approaches to using hydrogeomorphic templates in research and management.

Supplemental Keywords:

streams, lakes, hydrogeomorphology, nutrient cycling, hyporheic zone, sediment transport, flow regimes,, RFA, Scientific Discipline, Geographic Area, Ecosystem Protection/Environmental Exposure & Risk, State, Monitoring/Modeling, Environmental Monitoring, Ecology and Ecosystems, aquatic ecosystem, watershed, Idaho (ID), hydrogeochemical modeling package, sediment transport, modeling, phosphorus, biochemistry, river ecosystem, nutrient monitoring , hydrologic modeling

Progress and Final Reports:

  • Final