Since joining UD, Vargas has successfully secured over $1 million in grants as a principal investigator supported by the National Aeronautics and Space Administration (NASA), the United States Department of Agriculture (USDA), and the University of Delaware Research Foundation (UDRF). His research group has active study sites in Baja California, Delaware, and Maryland and collaborates with scientists across the United States, Asia, Europe and Mexico to understand how land ecosystems respond to climate variability, extreme events, and global environmental change.
Working at CANR, he has actively taken on multiple research endeavors. First, supported by a NASA grant, he is testing different approaches to improve a framework for monitoring, reporting and verification (MRV) to support implementation of Reduction of Emissions by Deforestation and Degradation (REDD+) across a gradient of forests in Mexico. This research involves collaboration with the US Forest Service, the Mexican Forest Service (CONAFOR) and multiple research institutions in Mexico.
Secondly, funded by a USDA grant, he is investigating the effect of extreme climate events on greenhouse gas fluxes in a watershed near UD’s campus by using state-of-the-art instrumentation for continuous measurements of carbon dioxide, methane, and nitrous oxide fluxes from soils. This research involves collaboration with Shreeram Inamdar, associate professor in the Department of Plant and Soil Sciences.
Lastly, funded by a UDRF grant, he is looking at the size, age, and use of nonstructural carbon reserves (NSC’s) in long-lived plants in the deserts of Baja California, Mexico. His results are providing insights about the physiological mechanisms of carbohydrate allocation and long-term plant survival in water-limited ecosystems.
“Several plant species in the central desert of Baja California can live for over 400 years under limited water availability and climate variability including decadal droughts,” said Vargas.
Preliminarily results show that new fine roots of desert palms and cactus are produced using “old” NSC reserves that are more than 20 years old. Vargas’ group has also found that the age of NSC reserves inside the plants can have a mean age of over 60 years.
“This means that these plants can store NSC reserves and keep them for a long time and then use them to produce new structures such as fine roots,” said Vargas.
Vargas said he is extremely lucky to have rapidly found friends among the UD community who support him and have made him feel welcome in Newark. His time here has already afforded him the opportunity to be exposed to and apply an array of various research techniques from multiple disciplines such as computer science, micrometeorology, remote sensing, and soil ecology.
Offering a sincere thanks to all of his new friends here at the CANR, he said “I have found amazing colleagues, leaders, and students across UD, and the working atmosphere is excellent to nourish and develop high quality research.”
As an undergraduate, Vargas studied biology in Mexico at the Universidad Nacional Autónoma de Mexico (UNAM), one of the largest universities in the world with over 350,000 students. It was there that he began his research career, studying nitrogen fixation of microbial mats in a tropical wetland at the Yucatan Peninsula.
He went on to earn a PhD at the University of California-Riverside where his research focused on how extreme events such as fires and hurricanes influenced carbon dynamics in regenerating forests. Through a combination of biometric forest measurements and experimental forest management techniques, he demonstrated the large capability of these forests to store carbon above and below ground.
Vargas also studied the effects of hurricane disturbance on CO2 fluxes within the soil, finding unprecedented rates of CO2 emissions from soil to atmosphere. Lastly, he demonstrated the unexpected capacity of plants to allocate old stored carbon to produce fine roots following a hurricane disturbance. In light of the east coasts’ late experience with Hurricane Sandy, Vargas’ past work shows the implications these weather phenomena’s have on the fate of stored carbon in plants.
In addition to this work, Vargas also worked on a side-project funded by the National Science Foundation studying belowground carbon dynamics in the San Jacinto Mountains of Southern California. This study allowed him to use a wireless network of soil sensors to measure CO2 fluxes and the relations with fine root dynamics. “One of the most exciting results is that we demonstrated that fast and continuous fine root measurements (daily and sub-daily) are needed to quantify and understand belowground carbon dynamics,” said Vargas.
Following his PhD, Vargas was a postdoctoral fellow at the University of California-Berkeley where he interacted with scientists around the world within FLUXNET, the international consortium of eddy covariance scientists. “My work focused on regional and global synthesis studies on water and CO2 fluxes of terrestrial ecosystems, combining measurements and ecological process-based models,” said Vargas.
Before arriving at UD, Vargas returned to Mexico to work as an assistant research professor at a national research center in Baja California, Mexico (CICESE). Here he led synthesis studies on ocean-to-atmosphere CO2 fluxes while also continuing measurements of water and CO2 fluxes in a shrub land ecosystem in Baja California. His interest in the effects of land use change on such fluxes also led him to coordinate the consolidation of the Mexican eddy covariance network (MexFlux), where his research group is working on a first generation of nationwide synthesis studies.
Article by Angela Carcione