Internships

Angelica She ’26

Major

Civil and Environmental Engineering

Project Title

Potassium Isotopes in Plants: A Hydroponic Investigation With Arabidopsis

Potassium is a vital plant nutrient and the most abundant cation in plants. In addition to regulating the opening of a plant’s stomata, through which gas is exchanged for photosynthesis, potassium also helps with pH maintenance and enzyme activation. Though potassium transport systems in plants are well studied, little is known about potassium isotope fractionation — the relative partitioning of light and heavy isotopes — associated with those transport systems. To fill this gap, we conducted a hydroponic growth experiment with Arabidopsis, a model plant, to investigate the relationship between potassium isotopic compositions and a plant’s transport system. I started the seeds in a control condition with plenty of potassium before transferring them to growth buckets supplied with nutrient solutions of varying potassium concentrations. I recorded plant growth, replenished nutrient solutions and sampled the plants after the experiment. I also dried and ground the plant parts into powders to be dissolved in nitric acid and analyzed for potassium concentration and isotopic composition. As the specks of seeds grew into tall plants with budding flowers, so, too, did my confidence in experimental work and aspirations to create environmental change through research, engineering or both.