Editing Bhabani Sankar Das (section)

==Research and expertise==
Professor Das's research is centred on soil as a foundational component of agricultural systems. His group addresses challenges in soil characterisation, water and nutrient management, and large-scale soil information delivery using advanced sensing and computational technologies.

===Soil physics and contaminant hydrology===
His foundational expertise lies in [[soil physics]], encompassing the study of water and solute transport processes in soils. His research addresses water flow, contaminant transport, and nutrient dynamics in rice paddy soils and other agricultural systems. He has applied modelling tools such as Hydrus-1D to simulate water and nutrient transport under alternate wetting and drying irrigation practices, contributing to improved water use efficiency in rice cultivation.<ref name="iitkgp-profile"/>

===Diffuse reflectance spectroscopy and soil characterisation===
A major contribution of Professor Das's group is the development and application of [[diffuse reflectance spectroscopy]] (DRS) as a rapid, non-destructive, and cost-effective alternative to conventional wet chemistry-based soil testing. His laboratory has developed calibrated spectral algorithms and [[spectral library|spectral libraries]] to estimate a wide range of soil properties — including texture, organic carbon, pH, micronutrients, water holding capacity, and cation exchange capacity — from spectral reflectance data. This work has been validated across multiple spatial and temporal scales and in collaboration with ICRISAT for applicability in smallholder farming systems across South Asia.<ref>{{cite web |url=https://pressroom.icrisat.org/new-discovery-in-rapid-soil-testing-for-smallholder-farms-using-diffuse-reflectance-spectroscopy |title=New Discovery in Rapid Soil Testing for Smallholder Farms Using Diffuse Reflectance Spectroscopy |publisher=ICRISAT Pressroom |access-date=2026-02-27}}</ref>

===Hyperspectral remote sensing===
Professor Das's group conducts extensive research in airborne and satellite [[hyperspectral remote sensing]] for the estimation of soil and crop parameters at landscape scales. His group has worked with data from sensors such as [[AVIRIS-NG]] for mapping soil salinity, texture, and other properties. Research from his group has also explored bidirectional reflectance distribution function (BRDF) corrections in hyperspectral data to improve soil property estimation accuracy.<ref name="iitkgp-profile"/>

===Digital soil mapping===
Professor Das is a leading contributor to [[digital soil mapping]] (DSM) in India. His group produced the first national-scale digital maps of key soil properties across India — including texture, pH, [[soil organic carbon]], water holding capacity, cation exchange capacity, and aggregate size distribution parameters — using legacy soil data and environmental covariates. These maps are a major resource for land resource assessment, food security research, and climate modelling in India.<ref>{{cite journal |last1=Reddy |first1=Nagarjuna N. |last2=Chakraborty |first2=Poulamee |display-authors=etal |title=Legacy data-based national-scale digital mapping of key soil properties in India |journal=Geoderma |year=2021 |doi=10.1016/j.geoderma.2020.114499}}</ref>

===Water remote sensing===
His group has also worked on water quality mapping using remote sensing approaches, including the development of water quality parameter maps for the [[Chilika Lake|Chilika lagoon]] in Odisha using satellite data.