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Soil, the largest terrestrial carbon reservoir, is central to climate change and relevant feedback to environmental health. Minerals are the essential components that contribute to over 60% of soil carbon storage. However, how the interactions between minerals and organic carbon shape the carbon transformation and stability remains poorly understood. Herein, we critically review the primary interactions between organic carbon and soil minerals and the relevant mechanisms, including sorption, redox reaction, co-precipitation, dissolution, polymerization, and catalytic reaction. These interactions, highly complex with the combination of multiple processes, greatly affect the stability of organic carbon through the following processes: (1) formation or deconstruction of the mineral–organic carbon association; (2) oxidative transformation of the organic carbon with minerals; (3) catalytic polymerization of organic carbon with minerals; and (4) varying association stability of organic carbon according to the mineral transformation. Several pieces of evidence related to the carbon turnover and stability during the interaction with soil minerals in the real eco-environment are then demonstrated. We also highlight the current research gaps and outline research priorities, which may map future directions for a deeper mechanisms-based understanding of the soil carbon storage capacity considering its interactions with minerals.

This paper gives an overview of soil ecosystem services, soil organic matter dynamics, models of soil organic matter, biotic and abiotic control of litter decomposition, patterns of soil biodiversity, and potential of soil carbon sequestration to mitigate climate change. Healthy soil provides a wide range of ecosystem goods and services and the value of the ecosystem services provided by soil biodiversity amounts to US $1.5 trillion per year. Soil texture, soil mineralogy and soil organic matter play an important role in the functioning of an ecosystem. The global carbon pools and fluxes, and soil and vegetation carbon pools at biome and regional level have been discussed. The organic matter inputs and soil carbon pools vary in different biomes and ecosystems. Soil organic carbon simulation models are being increasingly used to describe soil carbon dynamics. Climate, soil fauna and litter quality regulate the rates of litter decomposition at local, regional and global scale. Litter quality has emerged as the most important direct regulator of the rates and patterns of litter decomposition at the global scale. There is much interest to analyze the effect of litter diversity, climate change and invasive species on litter decomposition rates. Modern techniques of molecular biology and high resolution microscopy elucidate the structural and functional aspects of soil biodiversity. Sustainable management and conservation of soil biota is important for conserving global biodiversity, as soil communities are species rich and affect ecosystem processes. conservation agriculture, tree plantations on degraded lands, and agroforestry could enhance carbon storage in the soil-plant system. The integration of science, technology and traditional ecological knowledge can make substantial contribution to the science of soil ecology, ecosystem carbon management, and sustainability. [ABSTRACT FROM AUTHOR]

Estimating regional carbon (C) stocks and understanding their dynamics is crucial, both from the perspective of sustainable landscape management and global change feedback. This study combines remote sensing techniques and a coupled GIS-CENTURY model to estimate regional biomass C stocks and SOC dynamics for Guiera senegalensis shrub communities in Senegal''s Peanut Basin. A statistical model relating field-measured shrub aboveground biomass C at training plots to satellite image-derived shrub abundances was developed and used to estimate regional biomass C across a major part of the Basin. Regional SOC dynamics were modeled by coupling the CENTURY model and GIS databases. Significant correlation (r =0.73; p =0.05) was observed between aboveground biomass C and satellite image-derived shrub abundance at the training plots. Aboveground biomass C stocks ranged from 0.01 to 0.45Mgha−1 with an approximate total of 247,000MgC for the 3060km2 study area. CENTURY model predictions indicate that C sequestration in these systems is contingent on long-term effectiveness of non-thermal management of shrub residue and that the actual rates depend strongly on soil type and scenarios of future land management. Compared with the traditional “pruning-burned” management practice, returning prunings for 50 years would increase soil C sequestration by 200–350% without fertilization, and increase soil C sequestration by 270–483% under a low (35kgha−1 Nyr−1; 20kgha−1 Pyr−1) fertilization regime, depending on soil type and climate conditions. These results indicate that altered land management could contribute to transforming these degraded semiarid agroecosystems from a source to a sink for atmospheric CO2. [Copyright &y& Elsevier]