PhD student receives NSF grant

PhD student Megan Nasto, working with professor Cory Cleveland, recently received a Doctoral Dissertation Improvement Grant of $18,850 from the National Science Foundation. The grant provides partial support of doctoral dissertation research for improvement beyond the already existing project. PhD student Megan Nasto

For her PhD dissertation, Nasto is studying interactions among nitrogen and phosphorus through plant-microbial mutualisms in tropical rain forests. The tropics contain some of the largest, fastest growing and carbon (C) rich forests on Earth. As they grow, tropical trees store large amounts of atmospheric carbon dioxide (CO2) in their biomass, slowing the increase in atmospheric CO2 and hence the pace of climate change. Yet, all trees require large amounts of soil nutrients – especially nitrogen (N) and phosphorus (P) – to grow, and it remains unclear whether the supply of soil nutrients will be sufficient to meet the demands of predicted tree growth in the future. For example, soil P concentrations are relatively low in tropical forest soils, and some research suggests that low P supply may constrain increases in tree growth and C storage that are predicted with higher atmospheric CO2 concentrations. However, previous work suggests that some tropical trees may be better than others at accessing scarce nutrients because they have relationships with soil microorganisms that enable them to effectively scavenge nutrients. This research will explore how different tropical trees access soil nutrients and whether these microbial partnerships offer some trees an advantage over their competitors. Overall, this research will enhance an understanding of how tropical forests may respond to global environmental change.

Nasto also just was awarded a Smithsonian Tropical Research Institute Short-Term Fellowship that will support a project in Panama. She'll be looking at the same between plant-microbial mutualism, nutrient acquisition strategies, and soil nutrients as in the NSF DDIG project but under elevated levels of atmospheric carbon dioxide.