Introduction

Global warming with the burgeoning anthropogenic greenhouse gas (GHG) emissions (400 parts per million from 280 ppm CO2 emissions of pre-industrial era) has been altering the climate, eroding the ecosystem productivity and sustenance of water, affecting the livelihood of people. The anthropogenic activities such as burning fossil fuel, power generation, agriculture, industry, polluting water bodies and urban activities are responsible for increasing GHG footprint of which 72% constitute CO2. GHG footprint needs to be in balance with sequestration of carbon to sustain ecosystem functions. Forests are the major carbon sinks (about 45%) that aid in mitigating global warming [1, 2].
The land use land cover (LULC) dynamics leading to deforestation and land degradation is the prime driver of global warming due to the loss of carbon sequestration potential as well as emissions. The Western Ghats (Fig 1) are one among 36 global biodiversity hotspots and forests in this region sequester atmospheric carbon, which aid in moderating the global climate.
The region is endowed with 4,600+ species of flowering plants (38% endemics), 330 butterflies (11% endemics), 156 reptiles (62% endemics), 508 birds (4% endemics), 120 mammals (12% endemics), 289 fishes (41% endemics) and 135 amphibians (75% endemics). It covers an area of approximately 160,000 sq. km and extends from 8° N to 21° N latitudes and 73° E to 77° E longitudes. It is considered as a water tower of India due to numerous streams originates and draining millions of hectares. The rivers of WG sustains water ensuring water and food security of 245+ million people in the peninsular Indian states. The region has tropical evergreen forests, moist deciduous forests, scrub jungles, sholas, savannas including the high rainfall savannas of which 10% of the forest area is under legal protection.
The land use (LU) dynamics was assessed using temporal remote sensing data of Landsat 8 Operational Land Imager (OLI-30 m resolution) 2018 data integrated with field estimations and decadal land use (1985, 1995, 2005-100 m resolution) available from International Geosphere-Biosphere Programme (IGBP). The collateral data included the vegetation maps developed by French institute Puducherry, topographic maps (the Survey of India) and virtual earth data (Google Earth, Bhuvan). The carbon sequestration potential of forest ecosystems was assessed based on (i) published literature based on the standard biomass experiments and (ii) field based measurements collected across the forests of WG of Karnataka using transect based quadrat sampling techniques [1, 2].
The spatiotemporal LU analyses presented in Fig. 2, highlights the loss of forest cover due to anthropogenic pressure. The region had 16.21% evergreen forest cover in 1985, which is reduced to 11.3% in 2018. The region has 17.92%, 37.53%, 4.88% under plantations, agriculture, mining and built-up respectively. The increase in monoculture plantations such as Acacia, Eucalyptus, Teak, Rubber, developmental projects and agriculture expansions are the major drivers of LU changes. The region has lost 12% of interior (contiguous) forest cover during 1985 to 2018 with an increase of non-forest cover (11%). The interior forests (25% in 2018) are confined to major protected areas; edge forests are becoming more prominent due to sustained anthropogenic pressure (Fig. 3). Goa has experienced loss of large tracts of interior forest cover due to the indiscriminate rampant mining activities. The simulated LU (of 2018) was compared with the actual LU’s (of 2018), which shows a consistent result evident from higher accuracies (92.6%) and overall kappa (K(overall): 0.91, K(histo): 0.95, K(location): 0.95). The projected LU of 2031 (Fig. 4) highlights likely loss of evergreen forest with increases in agriculture cover (39%) and built-up area (5%) [1]. The large scale changes of agriculture and built-up cover are noticed as per Fig. 4, in the eastern Kerala, Tamilnadu, Maharashtra states of WG. The evergreen forest cover will only be 10% of the WG by 2031, which would threaten the sustenance of water and other natural resources [3, 4], affecting the food security and livelihood of people in the peninsular India.

Fig. 1 Study Area-Western Ghats, India	Fig. 2 LU analyses of WG from 1985-2018
Fig. 3 Forest fragmentation from 1985-2018	Fig. 4 Likely LU and fragmentation of WG by 2031
Fig. 5 Above ground biomass (standing biomass), carbon, soil carbon content and total carbon stock of WG