Research

I am an Engineering Geologist with interests in research pertaining to soil and rock mechanics, slope stability and erosion.  My current research can be divided into three broad categories (i) Hazard and risk evaluation using field methods and geospatial models, (ii) Soil erosion and its relation to weather pattern, and (iii) Wetlands soil and restoration efforts.

 

Hazard and risk evaluation using field methods and geospatial models

debris flow rockfall map  
Dr. Nandi in front of a paleo debris flow channel in southern Appalachian Highlands Examples of sites selected from high density clusters of poorly-rated slopes from an unstable slopes color-coded with rockfall risk map  

The spatial prediction of natural hazards is an important field of geosciences research.   Using geospatial models my work identifies areas susceptible to future slope instability hazards based on the knowledge of past landslide and debris flow events, terrain parameters, geological characteristics, hydrology, climate and possible anthropogenic environmental impacts that are associated with the presence or absence of such phenomena.   I also focus on risk assessment based on human exposure, economic and environmental loss induced by slope instability.

 

 

Soil erosion and its relation to weather pattern

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Gully Erosion in site at the Soil and Water outdoor lab at ETSU (image by Ingrid Luffman)

Soil erosion is a serious land degradation problem in Appalachian hillslopes, and is often associated with improper land management practices.  Erosion in these soils commonly takes the form of gully erosion in fine grained silty and clayey soils. Through series of collaborative studies our research team investigates the gully erosion morphology, soil characteristics and effect of weather pattern on gully erosion on a Appalachian hillslopes.

 


Wetland Soils and Restoration

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Sample pictures from Wetland Soil Study, Cherokee National Forest

Wetlands are defined as areas that are saturated frequently enough to support vegetation adapted for life in saturated soil conditions. Wetlands generally include swamps, marshes, bogs, fens, and similar saturated environments. Wetlands in the Cherokee National Forest has been impacted by a number of factors. Its history has been riddled with common flood occurrences, excess sedimentation from an eroding dirt road in the middle of the bog with a sloped elevation, land misuse from off road vehicles, and hunting stands built in the bog. Due to these factors, the wetland is in need of restoration. Before restoration can occur, a baseline soil analysis of hydric soil condition is necessary

 

Heavy metal contamination in soil and groundwater

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Mine soil study

Mining, manufacturing, and fertilizers, pesticides etc. can result in heavy metal contamination in soil and groundwater.  Heavy metals also occur naturally in bedrock and leach out to groundwater under specific geochemical conditions.  The spatial distribution of heavy metals in soil and groundwater is important in assessing soil quality and locating source of the contaminants.  My student researchers use combination of field, laboratory work, and geostatistical analysis using GIS to study heavy metal contaminations.