CAREER: Drying and warming impact interactions between organisms and ionomes

Freshwater ecosystems around the world are becoming warmer and drying more frequently. Although the words river or stream elicit images of permanent flowing water, most rivers and streams worldwide are not permanent. The immediate impacts of drying are often apparent (e.g., loss of water, dead fish), but less visually obvious effects of drying persist after water returns. A fish cannot live in water alone - it needs all the elements that make up its body and a suitable chemically balanced environment. But water returning to dried sediments kicks off multiple interacting chemical processes leading to the creation of a uniquely complex multi-elemental soup. Despite this complexity, studies of post-refill aquatic systems generally only chronicle surges of single elements (such as iron) rather than the 20-plus elements required for essential biological functions. Although life is similarly a complex combination of interacting chemical reactions, its recipe is far more constrained by what combinations and amounts of elements can sustain biological functions. These constraints lead to organisms having to constantly balance their internal elemental composition and altering that of their environment. This research will measure how prior drying events affect waterbodies after they refill through changes in biologically important elements and their effects on aquatic life in a warming world. It will also establish a critical foundation for understanding and predicting complex responses of aquatic systems to the consequences of global climate change. This education-research program directly involves the next generation of high school students from the largest school district in Kansas (USD 259) who are primarily from underrepresented and underserved communities (>70% come from homes of poverty). Students will receive hands-on scientific training, collect and analyze real-time environmental data, and earn college credit as part of a newly created field ecology course (dual listed with Wichita State University). Student-collected data will also be used to create five free-to-the-public lessons on data literacy geared towards helping high school students meet Next Generation Science Standards. These lessons will be produced as a collaboration between a professional education studio (Galactic Polymath), five paid high school teacher fellows, and WSU researchers on the project. A more complete understanding of how global climate change affects organisms in recovering ecosystems requires understanding of: (1) the large-scale generalities in how suites of elements (ionomes) jointly change in response to drying and rewetting; (2) how these changes affect organism-ecosystem feedbacks of elemental cycling; and (3) how these effects change with temperature. This program will expand our understanding in these areas, produce a trove of open access ionomic data and lay the foundation for future empirical-theoretical frameworks around multi-element dynamics across thermal regimes in functioning ecosystems. These experiments draw on the PI’s experience across taxa (single-celled organisms to vertebrates) to link responses in controlled laboratory experiments, more realistic but controllable outdoor mesocosms, and field-based studies of intermittent streams in the Flint Hills of Kansas. Research objectives at every level evaluate the interactive effects of changing climate forcers (drying and warming) on linked elemental cycles and their effects on organismal fitness. It is vital that we understand responses to multiple changing climate forcers while accounting for the broader context (e.g., post-refill water chemistry and community composition) of the ecosystem within which those organisms must function. These ambitious experiments span spatial and taxonomic scales beyond typical manipulative experiments in dynamic systems. The experiments and the data produced will be foundational to our understanding of how interdependent elements (the ionome) respond to environmental change and interact synergistically with organisms. This project is jointly funded by the Population and Community Ecology (PCE) Program in the Division of Environmental Biology and the Established Program to Stimulate Competitive Research (EPSCoR). This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.