Brian S. Ickes

New databases reveal 200 years of change on the Mississippi River system

Over the past two centuries, the Mississippi River system (MRS) has been dramatically altered to facilitate commercial navigation and provide flood control. Because of its long history of modification, rigorous measurements including maps, charts, surveys, and other data concerning the MRS are available from the past 200 years or longer. Comparison between historical reference conditions and modern conditions can document changes related to natural processes, human impacts, and river management practices and policies. To show these changes, we have assembled a hydrologic database of approximately 7 million measurements and a geospatial database consisting of 4878 map sheets dating back to 1765. The databases include nearly all available data sources for the navigable Mississippi River, the lower Missouri River, and the Illinois River (>4500 kilometers of waterways; see Figure 1, in the electronic supplement to this Eos issue; http://www.agu.org/eos_elec). We have digitized all 81 map sets and georeferenced 48 of those map sets, meaning that the maps have been referenced in physical space for use in a geographic information system. The purpose for constructing these databases is to centralize and standardize these data sources and to make them broadly available for research and management. In this article we describe the data, the databases, and their dissemination.

Long-Term Fish Monitoring in Large Rivers: Utility of “Benchmarking” across Basins

In business, benchmarking is a widely used practice of comparing your own business processes to those of other comparable companies and incorporating identified best practices to improve performance. Biologists and resource managers designing and conducting monitoring programs for fish in large river systems tend to focus on single river basins or segments of large rivers, missing opportunities to learn from those conducting fish monitoring in other rivers. We briefly examine five long-term fish monitoring programs in large rivers in the United States (Colorado, Columbia, Mississippi, Illinois, and Tallapoosa rivers) and identify opportunities for learning across programs by detailing best monitoring practices and why these practices were chosen. Although monitoring objectives, methods, and program maturity differ between each river system, examples from these five case studies illustrate the important role that long-term monitoring programs play in interpreting temporal and spatial shifts in fish populat...

Can data from disparate long-term fish monitoring programs be used to increase our understanding of regional and continental trends in large river assemblages?

Understanding trends in the diverse resources provided by large rivers will help balance tradeoffs among stakeholders and inform strategies to mitigate the effects of landscape scale stressors such as climate change and invasive species. Absent a cohesive coordinated effort to assess trends in important large river resources, a logical starting point is to assess our ability to draw inferences from existing efforts. In this paper, we use a common analytical framework to analyze data from five disparate fish monitoring programs to better understand the nature of spatial and temporal trends in large river fish assemblages. We evaluated data from programs that monitor fishes in the Colorado, Columbia, Illinois, Mississippi, and Tallapoosa rivers using non-metric dimensional scaling ordinations and associated tests to evaluate trends in fish assemblage structure and native fish biodiversity. Our results indicate that fish assemblages exhibited significant spatial and temporal trends in all five of the rivers. We also document native species diversity trends that were variable within and between rivers and generally more evident in rivers with higher species richness and programs of longer duration. We discuss shared and basin-specific landscape level stressors. Having a basic understanding of the nature and extent of trends in fish assemblages is a necessary first step towards understanding factors affecting biodiversity and fisheries in large rivers.

Spatially Explicit Modeling of Productivity in Pool 5 of the Mississippi River

The restoration and management of large rivers is difficult because such rivers have dynamic ecosystems and complex organic carbon cycles. Furthermore, energy flow is controlled by biotic and abiotic factors, similar to terrestrial systems, and also by hydraulic factors. There are three commonly discussed theories that attempt to describe productivity in large rivers, but none provides a generalized mechanism that can be applied across all rivers and all seasons. This chapter discusses a spatially explicit carbon-cycle model that simulates patterns of productivity in pool 5 of the Mississippi River. The model, developed using NetLogo (http://ccl.northwestern.edu/netlogo/), incorporates both ecological and hydraulic processes for the purpose of representing the complexity of the Mississippi River carbon cycle and pinpointing key sources of productivity within it. This model can serve as a simple and effective tool for use by researchers and students who are interested in studying river productivity, and it is readily adaptable to a variety of river ecosystems simply by substituting hydrology inputs such as maps of depth, velocity, and flow direction.