ESTIMATION OF TERRESTRAIL CARBON UPTAKE UNDER CLIMATE CHANGE AND LAND USE PRACTICES IN PAKISTAN

Abstract

The expansion of human enhanced greenhouse effect is increasing significantly with increasing emissions of CO2 from fossil fuels. Understanding the factors controlling land carbon up take is critical for projections of future climate. For calculating carbon pool acquired through photosynthesis, Dynamic Global Vegetation Model’s (DGVM’s) have been used. For this study LPJ-GUESS was used which is a process based dynamic vegetation terrestrial ecosystem model designed for regional or global studies. The model can predict structural, compositional and functional properties of the native ecosystem of major climate zones of the

earth. Pugh et al. (2015) assessed the effect of agricultural land management practices using LPJ- GUESS. The study measured carbon emissions under present and future climate change

scenarios by incorporating emissions from land use changes. The data from this study was used to assess land use emissions of Pakistan under different agricultural land management practices. The LPJ-GUESS simulations estimated for the past years from 1850-1950 showed that agricultural activities emitted less carbon dioxide that as compared to 1951-2012. Furthermore, for vegetation carbon, soil carbon and total carbon analyses suggest that for the RCP 8.5 future scenario the model predicts slightly lower carbon values compare to the RCP 2.6 future scenario. Key Words: Climate change, Dynamic Global Vegetation Models, LPJ-GUESS, Agricultural land management practices, Net Ecosystem Exchange, Carbon pool.