E2 offers professional services in ecological and environmental modeling. E2 offers more than 40 years of professional experience in the development, application, and evaluation of mathematical and computer simulation models used in support of the environmental sciences.

Individual Organisms. E2 provides the capability to develop and apply models that describe the biology and the ecology of individual organisms. E2 models have addressed the toxicology of Daphnia as well as the complex behavior of deer and Florida panthers.

Population Models. E2 demonstrates capabilities in modeling population dynamics. We have developed sophisticated, interactive population models using both demographic and bioenergetics descriptions of populations.

E2 has developed models of population dynamics of several aquatic and terrestrial organisms. Demographic population models have been developed by E2 to estimate the likelihood of invasive species (e.g., Asian longhorned beetle) establishment, risks posed by toxic chemicals to several species of fish, population-level impacts of commercial navigation on 30 species of fish in the Upper Mississippi and Illinois Rivers, and risks posed by hydrologic modification of the Florida Everglades on roseate spoonbills.

Bioenergetics models have been developed for periphyton, submerged rooted aquatic vegetation, unionid mussels, and several species of fish.  These models have been used to estimate risks posed by suspended sediments and entrainment mortalities associated with commercial navigation on the Upper Mississippi and Illinois Rivers.

Community/Ecosystem Models. E2 builds models that describe the complexities and dynamics of communities and ecosystems. These models have been developed in support of theoretical and applied ecology. E2 community and ecosystem models have also been used to assess ecological risks posed by various stressors, including habitat alteration, nutrient enrichment, hypoxia, and toxic chemicals.  

Habitat Modeling. E2 modelers have adapted existing habitat suitability index models to incorporate uncertainty in model parameters and model structure. This approach has been used to expand the assessment capabilities of clients interested in the anticipated outcomes of alternative planning and restoration activities in aquatic and riparian ecosystems. This approach has also been used to characterize the habitat implications of historical site development and operations at several U.S. Department of Energy facilities.

Landscape Modeling. E2 modelers have constructed a spatially explicit (rastor) model that simulates the uptake, recycling, and transport of nitrogen in a deciduous forest watershed (Walker Branch, Tennessee). The model has been analyzed to determine relationships between spatial scale, ecological complexity, and parameter uncertainty in assessing relationships between land-use and nitrogen cycling in this watershed.

E2 modelers have also produced spatially-explicit, dynamic models that describe habitat quality, quantity, and distribution at the landscape scale. This landscape simulator has been integrated with a demographic population model for the roseate spoonbill inhabiting the Everglades. This integrated landscape model is being used to determine the implications of water level management in South Florida on the longer term population sustainability for this important wading bird.