Analysis of fragmentation and disturbance regimes in south Gujarat forests, India

Forests, world over, have degraded, fragmented, and depleted as human population has swelled. In the present study, the forest fragmentation and the disturbance regimes were assessed in south Gujarat using satellite image-based forest and land use mapping followed by landscape analysis using Spatial Landscape Modelling (SPLAM) software. The on-screen visual interpretation of Resourcesat-1 LISS-III imagery facilitated in mapping of 9 forest and 12 non-forest classes. The observations revealed that 51.68 % of the forest area had low fragmentation while the rest had medium to high fragmentation. Among the vegetation types, 62.84 % of Tropical Moist Mixed Deciduous (TMMD) and 54.88 % of Tropical Mixed Dry Deciduous (TMDD) forests had low level of fragmentation whereas 15.5 % mangrove forest had high fragmentation. The study also showed that 72.53 % of the total forest area had low disturbance. High disturbance was noticed in Riverine forest (22.78 %) while TMMD forest was found to be less disturbed than TMDD forest. District-wise analysis revealed that forests of Valsad, Navsari and Bharuch were highly disturbed as well as fragmented whereas forests of The Dangs, Surat and Narmada had low disturbance and fragmentation. The study demonstrated important role of remote sensing, GIS, and SPLAM in forest/land use mapping and disturbance regimes and fragmentation status assessment.