Grant M. Casady

Adjunct Professor
Title:
Assistant Research ScientistArea of Expertise:
landscape ecology, disturbance ecology, dryland vegetation dynamics, time-series remote sensing, land surface phenology, invasive speciesCurriculum Vitae:
My primary research goal is to develop a better understanding of the causes and consequences of landscape-scale ecosystem change. Such changes are the result of many interacting factors, including past and present human activity, climate, and local hydrologic and topoedaphic properties. These factors produce patterns and processes that integrate across scales resulting in unique spatial and temporal interactions. I seek to better understand these dynamics by combining field-based and remotely sensed data using spatial analysis and modeling. The integration of field-based and remote sensing analysis allows me to evaluate ecosystems at multiple scales, integrating processes evident at the plot level into landscape and global scale dynamics. Examples of current projects illustrate my research interests:
- Post-wildfire vegetation dynamics. Vegetation dynamics in the wake of catastrophic wildfires are influenced by pre-fire land use and land cover, burn severity, post-fire climate, and a host of local environmental conditions. These factors combine in ways that are often unexpected, resulting in emergent behaviors that would not have been predicted by examining the influence of individual factors. My research seeks to elucidate the relationships among the factors influencing post-fire vegetation. An understanding of this interplay is important in tailoring management efforts to match current and probable future scenarios for goods and services provided by post-wildfire vegetation communities. This research is ongoing at sites in the United States, Israel, and Spain.
- Invasive plants and wildfire in the Desert Southwest. Desert ecosystems of the Southwest United States have had historically low fire frequency. The amount of fine fuels present in these ecosystems has increased due to a number of interacting factors, including changes in temperature and precipitation regimes, the introduction and spread of alien grass species, and recent increases in atmospheric CO2. Southwestern desert annual vegetation responds opportunistically to precipitation, and represents a variable fraction of ground cover against a matrix of soil backgrounds, making it difficult to detect with traditional remote sensing techniques. My research combines time-series remotely sensed vegetation data with ground measures of annual plant cover and biomass to describe changes in land cover phenology over time. By combining phenological information with climate and land use data, I hope to better describe the interannual dynamics of annual vegetation in the desert Southwest.
- Capacity building in the Senegal River Valley. The Senegal River provides resources for a large population in the countries of Senegal, Mauritania, Mali, and Guinea. Commercial and subsistence farming systems are dependent on the seasonal flooding of the Senegal River. Research currently underway aims to build the capacity of the Organisation pour la Mise en Valeur du Fleuve Senegal (Organization for the Management of the Senegal River Valley – OMVS) for the characterization of the hydrology, vegetation, and socio-economic impact of the current management efforts in the river basin. My research assesses the value of time-series MODIS vegetation data for monitoring the interactions between seasonal changes in water availability, crops, and water obligate invasive plants.
