13. Remote Sensing-Based Forest Biomass Assessment in Northwest Himalayan Landscape

Forests cover around one-third of the global land cover (4.03 billion hectares) (FAO 2010; Pan et al. 2013) and are among the richest ecosystems in terms of biological and genetic diversity (Köhl et al. 2015). Forests are considered as reservoirs of carbon, and it is stored as biomass (phytomass). The total amount of above- and belowground organic matter of both living and dead plant parts is called biomass (FAO 2005). Net primary productivity (NPP) is majorly accumulated as biomass. Around two-thirds (262.1 PgC) of the global terrestrial biomass is stored by the tropical forests (Pan et al. 2013; Negrón-Juárez et al. 2015). Therefore, forests act as one of the keystones of the global carbon cycle and play a vital role in designing the mitigating strategies for climate change and reducing the emission of greenhouse gases. Hence, forest biomass estimation is useful in quantifying the carbon stock, carbon emissions due to forest degradation and disturbances, carbon budget, productivity, forest planning and management and policy-making (Caputo 2009). Biomass monitoring in regular interval is utmost necessary for understanding the nature (source/sink) of the forest (Kushwaha et al. 2014). In addition, forests are vital sources of livelihood and economic development of any country (Köhl et al. 2015). Forest ecosystems offer numerous goods (timber, fodder, food, etc.) and ecological services (MEA 2005).