Resilience Scanner

Geospatial Mangrove Monitoring and Hydrodynamic Modeling System

Solution Overview

Geospatial monitoring tools have been deployed to track spatial and temporal changes in mangrove ecosystems along Thane Creek, Mumbai, combining satellite imagery analysis with hydrodynamic modeling to understand coastal dynamics.[1] This approach enables systematic assessment of mangrove distribution patterns, species composition, and the ecological role these forests play in coastal stabilization and flood attenuation.[1] The implementation addresses critical needs for evidence-based mangrove conservation in a rapidly urbanizing coastal environment where these ecosystems face competing pressures from development and natural processes.

Technical Components

The monitoring system utilized Landsat series satellite imagery for decadal change analysis from 1990 to 2017, combined with Sentinel-2 imagery for detailed species distribution mapping in 2017, processed through Semi-automatic Mapping of Land Cover (SMLC) methodology with QGIS-SCP software.[1] The ADCIRC hydrodynamic model was integrated to simulate tidal flooding and ebbing patterns toward mangrove areas, with validation conducted against in-situ observations of tides and currents.[1] In November 2017, the Maharashtra Forest Department signed an agreement with the Indian Space Research Organization (ISRO) to implement satellite imagery monitoring for mangroves across the state, including Mumbai.[3] The forest department utilizes ISRO's open source software to track mangrove changes, with images transmitted on a monthly basis to enable managers to identify locations of mangrove loss and gain.[3][4]

Implementation Details

The monitoring project with ISRO required an investment of Rs40 lakh from Maharashtra state authorities.[4] The geospatial analysis covered the entire Thane Creek mangrove system, which encompasses more than 59 square kilometers according to Forest Survey of India assessments.[3] Satellite imagery analysis between 2008 and 2021 revealed that 325 hectares of dense mangrove cover transitioned to sparse mangrove cover or converted to intertidal mudflats due to excessive erosion and sedimentation processes.[2] The monthly delivery schedule for satellite images provides forest managers with regular monitoring capabilities to detect changes in mangrove distribution patterns.[3] Analysis documented that between 1988 and 2017, urban development encroached on mangroves in several areas along Thane Creek, with the Deonar landfill spreading significantly and new residential and commercial development emerging along the northern stretches.[3]

Benefits and Impacts

Mangrove forest area in Thane Creek almost doubled from 79.14 km² in 1990 to 154.5 km² in 2017, with regeneration occurring toward both landward and seaward directions.[1] The hydrodynamic modeling demonstrated that with mangroves present, tidal currents attenuated 80% of their magnitude and favored sediment deposition in mangrove areas, which further enhanced mangrove growth and stabilized the coast.[1] Between 2008 and 2021, approximately 305 hectares of mangroves increased in density.[2] The sediment deposition process narrowed the channel and allowed some mangroves to spread closer to the center of Thane Creek over time.[3] Analysis revealed that mangroves in Thane Creek reached a saturation stage and achieved maximum growth toward the landward direction.[1] The dominance of Avicennia marina species confirmed increased anthropogenic activity along the landward side.[1]

Climate Adaptation Relevance

The monitoring system provides critical evidence of mangrove ecosystems' role in coastal flood protection, as modeling demonstrated that in the absence of mangroves, Thane Creek exhibited a perfect funneling effect with increased tidal amplification and strong flood currents, resulting in severe coastal inundation and erosion.[1] The 80% attenuation of tidal current magnitude by mangrove presence directly reduces flood risk for adjacent urban areas while promoting sediment deposition that enhances coastal stability.[1] Between 2010 and 2017, fluctuations in mangrove area distribution occurred due to different climatic conditions and anthropogenic activities, highlighting the need for continuous monitoring to track ecosystem responses to environmental pressures.[1]

Business Analysis

The Rs40 lakh investment in the ISRO partnership established a cost-effective monitoring framework leveraging existing satellite infrastructure and open source software platforms.[4] The monthly satellite image delivery model provides operational efficiency by enabling proactive identification of mangrove loss and gain locations without requiring extensive ground-based survey resources.[3] The Maharashtra Forest Department's agreement with ISRO represents a public-sector partnership model that distributes technical capabilities from national space agencies to state-level environmental management authorities.[3] The comparison between 1990 and 2020 documented that Thane Creek on Mumbai's eastern side has been shrinking, with more than 14 square kilometers of coastline witnessing mud deposition over three decades, as observed by the Mangrove and Marine Biodiversity Conservation Foundation of Maharashtra in 2021.[2]

Sources