History and Philosophy of the IRI

Taken from chapter 1 of Interdisciplinary research initiative: Hydrological and biogeochemical research in the Shingobee River headwaters area, north-central Minnesota, a U.S. Geological Survey Water Resources Investigations Report edited by T.C. Winter. (See Table of Contents)

Interdisciplinary investigation has long been a goal of some scientific institutions. This goal, however, is often elusive because discipline barriers are difficult to surmount. In some cases, scientists prefer to work with those in their own fields. In other cases, research follows discipline lines because of institutional structure and funding sources. The result is that many scientists from different disciplines do not come in frequent contact with one another. When scientists from different disciplines work at a common site, they commonly continue to work within their discipline, requiring a coordinator to integrate the results. This approach does little to break down discipline barriers. Less commonly is a concerted effort made to focus on a problem, where scientists from different disciplines are strongly encouraged to interact with one another from the outset of the study. Recognizing that most environmental problems require integration of many disciplines in order to understand the linkages between processes and to develop management solutions, a decision was made among Survey scientists to provide an incentive to foster closer interdisciplinary research, in which an attempt to integrate the research would be made from the outset, and throughout the study.

In late 1987, a group of scientists formed an Interdisciplinary Research Initiative (IRI) within the Water Resources Division. The group prepared a prospectus which had as its major theme that the management of the Nation's water resources requires knowledge of how atmospheric water, surface water, and ground water function as integrated systems. Fundamental attributes for the research initiative included; (1) the need for fundamental research on hydrologic and biogeochemical processes related to some of the most pressing environmental problems facing the nation, (2) selection of ecosystems that had comparative aspects, and (3) a long-term perspective. The fundamental study unit was to be a watershed, or watersheds, that included close interaction between physical, chemical, and biological aspects of atmospheric water, surface water and ground water. The watershed concept ties directly to USGS expertise in the study of the hydrologic cycle. The IRI was not to duplicate other long-term study efforts, such as the International Biological Program (IBP) or the Long-Term Ecological Research (LTER) program.

A basic premise of the IRI was that participating scientists would become involved on a voluntary basis and that they would provide their own funding. There were to be no constraints placed on the number of scientists participating, their discipline, or on duplication of effort. Indeed, a strength of the effort would be to provide the opportunity to do comparative evaluations of concepts, methods, and models. Annual meetings would be held to keep participants informed on research underway and planned, and to coordinate that research. 

It was decided to initially focus on lakes because they integrate many hydrologic processes that are present in their watersheds, and they preserve a record of past environmental change in their sediments. The organizing principle was to select one or more watersheds having two lakes with contrasting water residence times. The underlying hypothesis being that many processes in lakes are affected by the water residence time. Lakes having a short residence time generally have stream inputs and outputs, and therefore are dominated by external fluxes. In contrast, lakes having a long residence time generally are closed, and therefore are dominated by internal cycling. The contrasting water residence times were hypothesized to result in system-wide differences at all physical, chemical, and biological levels in the lake ecosystems, and are therefore the impetus for the comparative aspects of the IRI effort. Topics that could be studied stressing inter-lake comparison include, but are not limited to, dissolved organic carbon, alkalinity, lake hydrodynamics, composition of the plankton community, population turnover rates, and oxygen dynamics. While the unit of study was to be the watershed, a major focus would be on the lakes.

In the spring of 1988, a nationwide search was conducted to find a study area for the IRI effort. District offices of the USGS, and selected universities, were sent a list of selection criteria and were asked to propose candidate field sites. Water residence time was listed as the main criterion, but size of the study area and access to the study area were also important constraints to facilitate convenience and affordability. From 61 proposed sites across the United States, the committee selected the Shingobee River headwaters area in north-central Minnesota. This headwaters watershed contains seven lakes, but Williams Lake and Shingobee Lake best fit the selection criteria. Williams Lake has no stream inlet or outlet, it interacts only with the atmosphere and with ground water. Shingobee Lake has a stream inlet and outlet; therefore, the lake interacts with surface water as well as with the atmosphere and with ground water. Water residence time for Williams Lake is about 3 years, and for Shingobee lake it is about 7 months. The location of the study site is shown below.

Williams Lake had been under study by several members of the Water Resources Division for more than a decade, and an excellent data base, as well as instrumentation to measure atmospheric water, surface water, and ground water variables were in place. Shingobee Lake had not been studied previously. Climate stations and stream gages were established in the vicinity of Shingobee Lake in 1989. Sensors to measure water temperature, air temperature, vapor pressure, and wind speed were placed on a raft in the center of the lake. Sensors to measure long-wave radiation, short-wave radiation, air temperature, vapor pressure, wind speed, and wind direction were placed at a land station near the lake. A stage gage was placed on the lake, and stream gages were placed on the inlet and outlet streams.

Research on Williams and Shingobee Lakes, the Shingobee River, and a fen wetland has been underway since the spring of 1989. Presently, about 20 scientists participate in the IRI effort, most are from the USGS, but others are from the University of Minnesota, Twin Cities; University of Minnesota, Duluth; the University of California, Davis, and the Oak Ridge National Laboratory. To focus the research initially, the participating scientists identified three major study priorities for the IRI effort. These are concerned with: (1) processes associated with the carbon budgets of the two lakes, (2) physical, chemical, and biological interactions that formed and maintain the Little Shingobee fen, and (3) physical, chemical, and biological interactions that take place between the Shingobee River and its contiguous hyporheic zone. A site manager, supported by the USGS, was hired in 1989 to make routine and specialized measurements and sample collections, and to manage the general data base. 

This document (IRI Water Resources Investigations Report table of contents) provides a synopsis of the IRI effort, including; a description of the area, work underway, highlights of progress, and interactions sought from additional scientists. The papers herein represent only a brief overview of the work underway as of 1994. However, the authors have identified additional work that they believe would be useful in understanding the ecological interactions in the Shingobee River headwaters area. Thus, a goal of this document is to identify additional work, and to invite and encourage others to join the IRI effort.