Carbon sequestration and climate change mitigation

Abstract

This chapter examines the role of agroforestry in carbon sequestration (CS) and climate-change mitigation (CCM) based on the scientific hypotheses, research results, and observations accumulated so far. Since the emergence of climate change (CC) as a prominent global issue in the late twentieth century, agroforestry has received immense attention as a land-management strategy with considerable potential for addressing it. The underlying premise is that photosynthetic carbon capture by trees is an effective strategy for limiting the rise of CO2 concentrations across the globe, and agroforestry systems (AFS), compared with treeless agricultural systems, would lead to higher rates of CS. Following an overview of the commonly used technical terms, the chapter describes the extent, causes, and consequences of climate change; a summary of the global developments in the subject; the mechanisms of soil CS (SCS); and the importance of soil aggregates in SCS. Field research data on SCS reported from multilocational investigations in AFS in different ecological regions of the world as well as meta-analyses of reported results corroborate the higher C storage in AFS compared to single species cropping and grazing systems in both aboveground biomass and soils, especially at lower soil depths. Thus, the adoption of agroforestry practices can be a safe bet for CS and CCM. Brief accounts of some research initiatives and development paradigms related to soil carbon management for CCM are also included in the chapter. These include the potential use of biochar in AFS, and global activities such as Carbon Farming, One Trillion Trees Around the Globe, Regenerative Agriculture, and Soil Carbon Four per Mille (4p 1000).