Alison Appling, PhD
Biography
I am passionate about the process of transforming data into understanding. I participate in that process in two ways: As an ecologist and biogeochemist, I study the movement of energy, carbon, and nutrients through rivers, lakes, and floodplains to better understand how those ecosystems function. As a science communicator, I build interactive web-based data visualizations that tell a broader public audience about USGS research and activities.
What these data-rich projects have in common is that they require a lot of creativity, expertise, and collaboration...but also a lot of grunt work, because our datasets are often large and messy. My focus as a data scientist is on minimizing the grunt work in the data transformation process. To do this, I find existing software tools that support efficient data pipelines, build new tools when needed, and identify common patterns that help scientists to use those tools effectively. I share these tools and ideas primarily through collaboration with research and visualization teams, and occasionally via formal training efforts.
Science and Products
Application of the RSPARROW modeling tool to estimate total nitrogen sources to streams and evaluate source reduction management scenarios in the Grande River Basin, Brazil
Large-domain hydrological models are increasingly needed to support water-resource assessment and management in large river basins. Here, we describe results for the first Brazilian application of the SPAtially Referenced Regression On Watershed attributes (SPARROW) model using a new open-source modeling and interactive decision support system...
Miller, Matthew; de Souza, Marcelo L; Alexander, Richard B; Gorman Sanisaca, Lillian; de Amorim Teixeira, Alexandre; Appling, Alison P.Process-guided deep learning predictions of lake water temperature
The rapid growth of data in water resources has created new opportunities to accelerate knowledge discovery with the use of advanced deep learning tools. Hybrid models that integrate theory with state‐of‐the art empirical techniques have the potential to improve predictions while remaining true to physical laws. This paper evaluates the Process‐...
Read, Jordan S.; Jia, Xiaowei; Willard, Jared; Appling, Alison P.; Zwart, Jacob Aaron; Oliver, Samantha; Karpatne, Anuj; Hansen, Gretchen JA; Hanson, Paul C.; Watkins, William; Steinbach, Michael; Kumar, VipinDetecting signals of large‐scale climate phenomena in discharge and nutrient loads in the Mississippi‐Atchafalaya River Basin
Agricultural runoff from the Mississippi‐Atchafalaya River Basin delivers nitrogen (N) and phosphorus (P) to the Gulf of Mexico, causing hypoxia, and climate drives interannual variation in nutrient loads. Climate phenomena such as El Niño–Southern Oscillation may influence nutrient export through effects on river flow, nutrient uptake, or...
Smits, Adrianne P; Ruffing, Claire M; Royer, Todd V; Appling, Alison P.; Griffiths, Natalie A.; Bellmore, Rebecca; Scheuerell, Mark D; Harms, Tamara K; Jones, J.B.Metabolic rhythms in flowing waters: An approach for classifying river productivity regimes
Although seasonal patterns of ecosystem productivity have been extensively described and analyzed with respect to their primary forcings in terrestrial and marine systems, comparatively little is known about these same processes in rivers. However, it is now possible to perform a large‐scale synthesis on the patterns and drivers of river...
Savoy, Philip; Bernhardt, Emily S.; Appling, Alison P.; Heffernan, James B.; Stets, Edward G.; Read, Jordan S.; Harvey, JudsonEnhancement of primary production during drought in a temperate watershed is greater in larger rivers than headwater streams
Drought is common in rivers, yet how this disturbance regulates metabolic activity across network scales is largely unknown. Drought often lowers gross primary production (GPP) and ecosystem respiration (ER) in small headwaters but by contrast can enhance GPP and cause algal blooms in downstream estuaries. We estimated ecosystem metabolism across...
Hosen, Jacob D.; Aho, Kelly S.; Appling, Alison P.; Creech, E.C.; Fair, Jennifer H; Hall, Robert O Jr.; Kyzivat, Ethan; Lowenthal, Rachel; Matt, Serena; Morrison, Jonathan; Saiers, James E.; Shanley, James B.; Weber, Lisa; Yoon, Bryan; Raymond, Peter A.The metabolic regimes of 356 rivers in the United States
A national-scale quantification of metabolic energy flow in streams and rivers can improve understanding of the temporal dynamics of in-stream activity, links between energy cycling and ecosystem services, and the effects of human activities on aquatic metabolism. The two dominant terms in aquatic metabolism, gross primary production (GPP) and...
Appling, Alison P.; Read, Jordan S.; Winslow, Luke A.; Arroita, Maite; Bernhardt, Emily S.; Griffiths, Natalie A.; Hall, Robert O.; Harvey, Judson W.; Heffernan, James B.; Stanley, Emily H.; Stets, Edward G.; Yackulic, Charles B.Overcoming equifinality: Leveraging long time series for stream metabolism estimation
The foundational ecosystem processes of gross primary production (GPP) and ecosystem respiration (ER) cannot be measured directly but can be modeled in aquatic ecosystems from subdaily patterns of oxygen (O2) concentrations. Because rivers and streams constantly exchange O2 with the atmosphere, models must either use empirical estimates of...
Appling, Alison P.; Hall, Robert O.; Yackulic, Charles B.; Arroita, MaiteThe metabolic regimes of flowing waters
The processes and biomass that characterize any ecosystem are fundamentally constrained by the total amount of energy that is either fixed within or delivered across its boundaries. Ultimately, ecosystems may be understood and classified by their rates of total and net productivity and by the seasonal patterns of photosynthesis and respiration....
Bernhardt, Emily S.; Heffernan, Jim B.; Grimm, Nancy B.; Stanley, Emily H.; Harvey, Judson; Arroita, M.; Appling, Alison P.; Cohen, M.J.; McDowell, William H.; Hall, R.O.; Read, Jordan S.; Roberts, B.J.; Stets, Edward G.; Yackulic, Charles B.