Abstract: Advances in different -omics technologies have revolutionized biological research by enabling high-throughput monitoring of biological processes at the molecular level and their responses to environmental perturbation. Metabolomics is a fast-emerging technology in systems biology that aims to profile small compounds within a biological system that are often end products of complex biochemical cascades. Thus, metabolomics can enable discovery of the genetic basis of metabolic variation by linking the genotype to the phenotype. Despite increasing accessibility of multi-omics technologies, integration of multi-omics data in analysis pipelines remains a challenge especially in the environmental field. In addition, there are still many associated bottlenecks to overcome in metabolomics before measurements will be considered robust. In this talk, I will go over current efforts in my lab that builds on ten years of analytical experience to develop comprehensive, open-source, command-line based pipeline for metabolomics data analysis. I will then spend the rest of the lecture describing how such data can help us disentangle organisms’ metabolic responses and acclimation to environmental gradients. This includes our work across three contrasting different ecosystems: the Tropical Rainforest Biome of Biosphere 2 (B2), Saguaro Desert National Park and peatland ecosystems.

Abstract: This talk draws together concepts in Black geographies and critical physical geography to examine the linkages between racial and environmental histories in Black environmental justice communities along the U.S. Gulf Coast. Specifically, this talk considers the notion of ecological memory, a natural science concept that refers to how past states or processes influence present or future responses in ecological communities, and its compatibility with threads within Black geographies and Black studies, in particular the afterlife of slavery. The afterlife of slavery refers to the precarity and devaluation of Black life set in motion by chattel slavery. Heeding calls within critical physical geography to take seriously the biophysical and social co-constitution of landscapes, I put forth the concept of the biophysical afterlife of slavery to describe how the precarity and devaluation of Black life has impacted the natural environments in which these Black lives exist. In this talk, I will discuss a framework I have developed that draws together the reconstruction of environmental histories with analyses of the past, present, and future of the biophysical afterlife of slavery: using dendrochronology and trees as archives of the biophysical afterlife of slavery, as well as witnesses to Black life and sense of place in environmentally precarious spaces over time. This research focuses on a case study of Port Arthur, Texas, a historically Black community nestled in what the US Environmental Protection Agency calls “the largest oil refinery network in the world”.

In this talk I will present results from a field-based terrestrial analog study involving characterization of the sedimentology and geomorphology of a periglacial alluvial fan in the Richardson Mountains, Northwest Territories, Canada. I will (1) qualitatively describe the range of sedimentary processes occurring on a periglacial alluvial fan and compare them to prior observations, (2) report measured flow discharges and runoff rates that occurred during a summer storm event, and (3) show that melt rates suggested for Mars are capable of entraining and transporting appreciable amounts of sediment by fluvial processes.

University of California, Santa Barbara

University New South Wales

Sensing Groundwater from a Distance: Harnessing Satellite and Ground-based Geophysics to Model Hydrogeologic Fluxes and Their Impact on Natural and Human Systems

Climate change, population growth and land use change are increasing the scarcity of surface water supplies and driving greater demand for groundwater resources. This trend has led to the ongoing depletion of many of the world’s aquifers. While many have observed regional groundwater depletion, the processes driving this depletion, and its effect on aquifer dynamics, are poorly understood. One major barrier to improving understanding of these processes is a lack of data at appropriate resolution and scale. The booming satellite industry is providing petabytes of earth observational data that have the potential to answer many of these scale- and resolution- dependent questions, but relating these disparate datasets to hydrogeologic systems requires an improved fundamental understanding of the system properties linking aquifer processes to land surface dynamics. For example, Interferometric Synthetic Aperture Radar (InSAR) can be used to estimate earth deformation with cm- to mm- accuracy, but the mechanisms linking aquifer dynamics to ground deformation are complex, non-linear and vary with time. Evapotranspirative flux, a major component of groundwater use, can be modeled with thermal satellite imagery, but these models alone often do not adequately explain groundwater demand, indicating complex inter-relationships between evapotranspiration, precipitation, infiltration, groundwater use and surface water use. In this talk, I will discuss several ongoing projects that seek to address these challenges, including both process-based and data-driven models that integrate in-situ data, as well as ground-based and satellite geophysics to identify key, scale-dependent drivers of groundwater flux, explore how temporally varying hydrologic parameters can alter aquifer dynamics, and link groundwater over-use to impacts on water quality.

Abstract: Plastic pollution threatens the health of humans and aquatic and terrestrial ecosystems globally. Proposing coping strategies and solutions to this threat requires a clear understanding of the processes controlling the fate and transport of mismanaged plastics at multiple scales, going from watersheds to regions and even continents. River corridors are the primary conveyors and traps for mismanaged plastic produced within the landscape and eventually released into the ocean. During this talk, I explore the primary sources of plastic pollution globally and present the results of a new flow and transport model for plastic waste in riverine environments. We found that only a fraction of the mismanaged plastic entering rivers since the 1950s (roughly 0.25%) will be delivered to the ocean by 2100, with most of the plastic being sequestered in freshwater ecosystems. The patterns of plastic accumulation and its residence time are strongly controlled by the (i) topology and geometry of the river network and (ii) the relative location and trapping efficiency of flow regulation structures, primarily large dams. Our modeling results highlight the role of rivers as major sinks for plastic waste and the need for targeted remedial strategies that consider the river network structure and anthropogenic regulation when proposing intervention measures and sampling efforts to optimize the gains and set realistic expectations.