Use of earth observation satellite data to assess disturbance in perennial ecosystems of tea growing areas of Assam
Student name: Ms Akanksha Balha
Guide: Mr Chander Kumar Singh
Year of completion: 2012
Host Organisation: RRSC (East)/ NRSC, Indian Space Research Organisation
Supervisor (Host Organisation): Dr D. Dutta
Abstract: Large-scale ecosystem disturbances (LSEDs) have major consequences on the global carbon
cycle as large amounts of CO2 and other trace gases from terrestrial biomass loss are emitted to
the atmosphere during disturbance events. Understanding Global Carbon cycle faces a
uncertainty due to i) the lack of a satisfactorily proven methodology to monitor and understand
LSEDs and ii) high spatial and temporal variability of atmospheric emissions.
In the present study, MODIS Global Disturbance Index (MGDI) algorithm is used which is
designed for large-scale, regular, disturbance mapping using coupling of Moderate Resolution
Imaging Spectroradiometer (MODIS) Land Surface Temperature (LST) and MODIS Vegetation
Index data. The MGDI uses annual maximum composite LST data to detect fundamental changes
in land-surface energy partitioning, while avoiding the high natural variability associated with
tracking LST at different time frames - daily, weekly, or seasonally MGDI algorithm has been
used from 2001-2011 across the Assam state of India. MGDI testing has been done with respect
to the disturbances occurred by floods and other events in the areas of tea gardens, protected
areas etc, Statistical analysis of the spatial data and MGDI images revealed that MGDI has
proved to be efficient in detecting the locations and spatial extent of disturbance events. Results
show that in year 2003, flood and forest fire affected 72.69 sq km area and 796.37 sq km area
respectively in Assam.
Key words: LSED, Global Carbon cycle, MODIS, MGDI, protected areas,
