Remote Sensing and Geographic Information System Based Mapping of Flood Impact on Banana Orchards in Lower Gangetic Plains of Bihar, India

Bananas are grown in the lower Gangetic plains of Vaishali, Bhagalpur, Purnea, and Katihar
districts in Bihar, which suffer flooding during the rainy seasons. Prolonged water logging in
lowlands provides a vulnerable zone for fungal and bacterial infestation in banana orchards,
leading to a reduction in fruit yield. The assessment of flood inundation and vulnerability
hotspots in banana orchards faced obstacles, such as the dynamic and complex nature of the
monsoon, infestation in plants, and yield losses in fruits. Hence, multispectral, hyper spectral,
and thermal data were utilized for visual interpretation, image processing, and extraction of
geospatial information aimed at mitigation. The study provided valuable insights into the
temporal changes in flooding and water logging in the specific area where banana orchards
are at higher risk, contributing to the development of strategies for mitigating yield losses in
flood-prone areas. Keeping these views in mind, the present study was carried out to assess
the temporal changes in flood inundation during the monsoon using satellite data of the
Moderate Resolution Imaging Specro-radiometer (MODIS V6, 2021) and to analyze the site-
specific vulnerable hotspots where banana orchards may be badly affected due to floods.
Results revealed that out of the total geographical area of Naugachhia subdivision (86982 ha),
only 2541.36 ha (0.97%) are under banana orchards. The analyzed data shows that the
maximum area under banana orchards was found in Kharik block (1157.83 ha), followed by
Naugachhiya block (702.12 ha), Bihpur block (379.57 ha), Gopalpur (189.6 ha), Narayanpur
(63.85 ha), Ismailpur (40.92 ha), and Rangra Chowk (7.47 ha), where, banana orchards were
badly affected by bacterial and fungal diseases in Gopalpur (115.59 ha), Ismailpur (31.28 ha),
and Rangra Chowk (1.25 ha).