Globally carbon dioxide concentration in the atmosphere has increased from 280 ppm in 1750 to 400 ppm in 2014 and is expected to reach 700 ppm in 2085, primarily due to human activities. Removing atmospheric carbon and storing it in the terrestrial biosphere is one of the options, which have been proposed to compensate carbon dioxide (green house gas) emission. This study emphasized developing model for carbon sequestration in biomass, and for evaluation and modification of carbon model (century soil carbon models), that will help to predict the impact of different management practices and land use change on sequestration of the atmospheric CO2 in plant biomass and soils. This book aims to describe different ecological models used for terrestrial carbon sequestration estimation in a most elementary manner so that the students/teachers/researchers in Ecology, Environmental Science, Environmental Modelling, Soil Science can understand without mathematical and statistical expertise.