ABSTRACT

The study on assessment of forest biomass and degradation was conducted in the Yellapur forest division of Uttara Kannada district, geographically positioned between 74° 25' to 75° 6' East longitudes and 14° 44' to 15° 7' North latitudes. A Land Use and Land Cover map of these forest types developed using Sentinel-2 satellite data processed through Google Earth Engine. The semi-evergreen forest in the Yellapur forest division has the highest vegetation coverage (91.71%), while the dry deciduous forest has the most extensive agricultural land (28.64%) and built-up area (3.98%). The moist deciduous forest stands out with the highest overall built-up area (15.79%).
The spatial and temporal analysis for the Yellapur forest division from 2000 to 2023 reveals significant changes. Vegetation, which covered 178,108 ha (90.35%) in 2000, decreased to 160,018 ha (81.68%) by 2023, 8.67 per cent reduction due to deforestation, agricultural expansion and infrastructure development. Agricultural land increased from 12,369 hectares (6.27%) in 2000 to 16,976 ha (8.61%) in 2023, driven by population growth and rising food demand. The built-up area expanded significantly from 4,564 hectares (2.32%) in 2000 to 17,413 hectares (8.83%) in 2023 mainly due to urbanization and infrastructure growth.
The Yellapur forest division experienced notable degradation across various forest types between 2023 and 2024. The dry deciduous forest saw significant declines, including a reduction in basal area by 2.38 m² ha⁻¹, biomass by 13.038 t ha⁻¹ and carbon stock by 6.146 t ha⁻¹ along with a notable increase in the number of dead trees due to disease and cutting. In contrast, the semi-evergreen forest exhibited relatively minor degradation.