Sustainable Land Management for Mitigating Climate Change

107. Adoption of SLM through Economic Incentives: The strategy of SCS through the deliberate choice of SLM practices for sequestering and trading of C credits to create another income stream for land users is called “farming soil C”. The objective is to grow (increase) soil C pool and trade it as a farm commodity for financial gains. The rate of SCS depends on climate, land use, soil properties and choice of specific SLM technologies. The rate is generally more for cool and humid than warm and dry climates, heavy-textured soils containing predominantly high activity clays (HAC) than light-textured soils with low activity clays (LAC), soils managed with SLM practices than those cultivated with extractive farming, restorative farming systems involving judicious use of crop residues and biosolids (manure, compost) than those where residues are removed and biosolids are rarely used and, degraded and desertified soils with high SOC deficit than those containing relatively high initial SOC pool. Commonly observed rates of SOC sequestration listed (see Table 14) provide general guidelines, but the site-specific rates must be established through local studies. Estimates of regional and global potential of soil carbon sequestration in croplands are shown in Table 31. These estimates are tentative and can be improved with increase in data availability especially for developing countries. In the best case scenario, the global potential of SCS is about 1Gt C/yr (Table 31). There exists an additional potential of 1 Gt C/yr in the forest biomass, and 1 Gt C/yr through the fossil fuel off-set of anthropogenic emissions through establishment of forest plantations. The technical potential of C sequestration in the terrestrial biosphere is much greater, and maybe as much as 6 to 10 Gt C/yr (Table 32).

108. With the current prices, the extra income generated though C trading is rather small (often <1 $/acre). At this price, it is doubtful whether the revenues generated through C sequestration can substantially increase rural household income in Latin America, Africa and Asia. Thus, the opportunity cost (i.e., trade-offs) of adopting C-enhancing SLM practices must also be taken into account.