• SUNIL KUMAR

Articles written in Journal of Earth System Science

• Land subsidence mapping and monitoring using modified persistent scatterer interferometric synthetic aperture radar in Jharia Coalfield, India

Subsidence has been adversely affecting Jharia Coalfield (JCF) for the last few decades. This study attempts to show the feasibility of the modified Persistent Scatterer Interferometric Synthetic Aperture Radar (PS-InSAR) technique with C-band SAR data to investigate the slow surface deformation caused by coal mine fire and underground mining activities in JCF. Also, a multi-temporal analysis of SAR images of ENVISAT ASAR has been carried out for monitoring and mapping of temporal land subsidence of the area under study. The modified PSI technique has proven its ability to detect land subsidence over the vegetated and rural areas. It also resolves low spatial density of permanent scatterers by considering partially correlated scatterers as permanent scatterers (PSs) and extracting information from these PSs. The study has been concentrated towards detecting continuous slow rate subsidence of five major sites of JCF. The maximum rate of slow deformation among all sites is recorded as 29 mm/year with a cumulative subsidence value of 90 mm. Field validation of subsidence results obtained through PS-InSAR is correlated with the previously published report and the master plan of JCF, showing subsidence locations. Conclusively, the adopted methodology is practically feasible for detection, monitoring and mapping of slow deformation using C-band SAR data in coal mine area.

• Geoecological integrity index for assessment and prioritisation of watersheds in the Indian northwestern Himalayan region using geoinformatics

Biotic, abiotic and anthropogenic factors are considered in isolation for prioritisation of watersheds. Instead, it requires a multidisciplinary geoecolocical approach. The geoecology based prioritisation provides opportunities to assess the region by evaluating these multiple factors in combination. Thus, Geoecological Integrity Index (GII) was developed for prioritisation of Baner River watersheds of Indian northwestern Himalayan region by integrating biotic, abiotic and anthropogenic factors as the region is facing geological and ecological instability. Forest cover density and net primary productivity were used as biotic factors and drainage morphometry, soil erosion, and patches were used as abiotic factors. Population density of the watershed was considered as an anthropogenic factor. Weighed overlay analysis was carried out to understand the influence of each of these factors on watershed prioritisation. These factors were integrated to arrive at cumulative weights (GII) for micro-watersheds. With the help of GII, out of 110 micro-watersheds, 11 were prioritised as very high actionable, 32 as high actionable, 52 as moderately actionable and 15 as of minimal action, requiring suitable actions in a prioritised manner to conserve and manage. The study presents an approach for geoecological assessment of watersheds that can be replicated in watersheds of other Himalayan regions or areas having similar geoecological conditions.

$\bf{Highlights}$

$\bullet$ Geoecological Integrity Index (GII) was developed for prioritisation of watersheds in Indian north-western Himalaya.

$\bullet$ GII was developed considering biotic, abiotic and anthropogenic factors, which are generally treated in isolation.

$\bullet$ Geoecological factors were integrated to arrive at cumulative weights (GII) for micro-watersheds.

$\bullet$ Out of 110 micro-watersheds, 11 were prioritised as very high actionable, 32 as high actionable, 52 as moderately actionable and 15 as of minimal action, requiring suitable actions for its conservation and management.

$\bullet$ Study provided an approach for geoecological assessment of watersheds that can be replicated in any other watersheds having similar conditions.

• # Journal of Earth System Science

Volume 130, 2021
All articles
Continuous Article Publishing mode

• # Editorial Note on Continuous Article Publication

Posted on July 25, 2019