Staying In The Current and Looking Towards The Future
Water defines life across the Coastal Plain. Water is the lifeblood of streams, rivers, and wetlands, supplies irrigated agricultural demands, and creates crucial habitat for rare and endemic plants and animals across the region. The human stress and demand for water resources are high and the future of water in the Coastal Plain is murky.
Bringing clarity to the murky waters is the research aim of the Aquatic Sciences Lab at The Jones Center at Ichauway: to understand the demands of water and how life in water responds. The lab, led by Dr. Nick Marzolf, started in January 2024 and will build on the strong foundation established by the Water program at The Jones Center as a focal point of water issues in Georgia and the Apalachicola-Chattahoochee-Flint (ACF) Basin (Figure 1). As the demands on water resources increase, the climate changes, and management actions occur at broad scales, documenting how creeks, rivers, wetlands, and reservoirs and their organisms respond to changes in the resource is an important contribution to the community of southwest Georgia.
Changes in aquatic ecosystems can be hard to find. While examples like algal blooms are stark and can be a symptom of high nutrient concentrations, other changes require sustained data collection over many years and at many sites. For one, the volume of water, either in surface water (creeks, rivers, wetlands) or in groundwater, is an essential baseline measurement that we rely on and is supported through taxpayer supported data collection by the United States Geological Survey (USGS). The USGS has recorded streamflow at sites around The Jones Center dating back to the 1930s, allowing us to evaluate changes in flow over nearly a century. These data contribute to understanding changes in minimum flow conditions and the demand for water resources in a watershed that has experienced an increase in agriculture since the 1970s (Figure 2, Golladay et al. 2007).
At play in the ACF basin are drivers that act in confounding ways. Local and regional demands on water resources are clear, and layered on top are the effects of climate change. Warmer air temperatures are predicted across the region, but rainfall projections are less clear. Extreme conditions, like droughts and floods, are expected to become more frequent. The residents of the ACF are becoming wise to this uncertain future and are implementing large-scale conservation practices (https://ga-fit.org/) to conserve water under drought conditions to preserve water resources and the diverse animals that call the region home, including freshwater mussels. Thus, part of the task of our lab is to help document changes in water resources in the ACF basin and how the organisms are responding to demands in water resources.
In addition to data collected by the USGS, we maintain and collect our own suite of data that help describe how creeks, rivers, and wetlands are influenced by variability in flow conditions. The lab maintains a long-term water quality monitoring program, where we collect stream chemistry samples from across the Flint River and its tributaries every month. With these data, we explore patterns in nutrient concentrations and the downstream transport of essential elements for life, like carbon, nitrogen, and phosphorus. In contrast to samples collected every month, we use advances in technology to collect high-resolution data with sensors placed in creeks. A key parameter we focus on is the concentration of dissolved oxygen (DO). Like humans, many organisms in creeks require oxygen to breathe (though underwater!) and we use these data with models to understand how the entire creek ‘breathes’, exchanging DO between plant production and respiration of organisms (Figure 3). We can also examine how often and for how long DO falls below concentrations that are potentially harmful to life in creeks.
Literature Cited:
Golladay, S. W., D. W. Hicks, and T. K. Muenz. 2007. Stream flow changes associated with water use and climate variation in the Lower Flint River basin, southwest Georgia. Proceedings of the 2007 Georgia Water Resources Conference.
