A. Land Use Conversion 59. Land use affects soil quality and the terrestrial/ecosystem C pool through its impact on both the biomass and SOC pools. Land use affects NPP through alterations in soil moisture and temperature regimes, changes in elemental cycling and nutrient availability. In the Loess Valley of China, for example, Gong et al. (2006) documented significant impacts of land use on soil quality, NPP, and ecosystem C pool. Developing strategies that foster SLM in fragile soils (e.g., Loess Plateau in China) is important to enhancing the ecosystem C pool. In Thailand, Gnanaverajah et al. (2008) assessed the ecosystem C pool for 11 different land use systems. The biomass C pool was 247.9 t C/ha for rubber, 189.4 t C/ha for mixed orchard, 159.1 for eucalyptus, 139.2 t C/ha for coconut, and 12.9 t C/ha for rice paddy. The data from Minas Gerais, Brazil, show that conversion of degraded to improved pastures and establishment of plantations on degraded lands can enhance the SOC pool (see Table 12). Thus a perennial land use, established on degraded land, is an important option to adapt to CC while enhancing the ecosystem C pool and NPP. B. No-Till Systems 60. The choice of seedbed preparation, of methods and timing of tillage operations, is important to adaptation to and mitigation of CC. Crop residues constitute more that 50% of the agricultural biomass (Smil, 1999), and are important to recycling of C and nutrients. world’s Effectiveness of NT farming on improving soil quality depends on retention of crop residue mulch. It is widely documented that conversion of conventional tillage (CT) to NT farming, with use of crop residue mulch and cover crops in the rotation cycle along with INM, conserve soil
A. Land Use Conversion 59. Land use affects soil quality and the terrestrial/ecosystem C pool through its impact on both the biomass and SOC pools. Land use affects NPP through alterations in soil moisture and temperature regimes, changes in elemental cycling and nutrient availability. In the Loess Valley of China, for example, Gong et al. (2006) documented significant impacts of land use on soil quality, NPP, and ecosystem C pool. Developing strategies that foster SLM in fragile soils (e.g., Loess Plateau in China) is important to enhancing the ecosystem C pool. In Thailand, Gnanaverajah et al. (2008) assessed the ecosystem C pool for 11 different land use systems. The biomass C pool was 247.9 t C/ha for rubber, 189.4 t C/ha for mixed orchard, 159.1 for eucalyptus, 139.2 t C/ha for coconut, and 12.9 t C/ha for rice paddy. The data from Minas Gerais, Brazil, show that conversion of degraded to improved pastures and establishment of plantations on degraded lands can enhance the SOC pool (see Table 12). Thus a perennial land use, established on degraded land, is an important option to adapt to CC while enhancing the ecosystem C pool and NPP. B. No-Till Systems 60. The choice of seedbed preparation, of methods and timing of tillage operations, is important to adaptation to and mitigation of CC. Crop residues constitute more that 50% of the world’s agricultural biomass (Smil, 1999), and are important to recycling of C and nutrients. Effectiveness of NT farming on improving soil quality depends on retention of crop residue mulch. It is widely documented that conversion of conventional tillage (CT) to NT farming, with use of crop residue mulch and cover crops in the rotation cycle along with INM, conserve soil
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