Root Carbon Sequestration and Its Efficacy in Forestry and Agroforestry Systems: A Case of Populus euramericana I-214 Cultivated in Mediterranean condition
Keywords:carbon distribution; carbon LER; hybrid poplar; Mediterranean region; sequestered Carbon
Poplar is one of the most popular species of forestry and agroforestry land-use worldwide. It is currently assuming a growing importance for timber, bioenergy production and Carbon sequestration. Soil Carbon accumulation is associated with root litter, whereas available studies are disproportionate on root system in this species. Therefore, the study aimed at finding how much root Carbon, a hybrid poplar species (Populus euramericana I-214) sequestered in Forest System (FRS) and Agroforest System (AFS) by using soil excavation and root coring methods. A suitable conversion factor was used to get sequestered Carbon estimated from biomass. Carbon was distributed in maximum length, breadth and depth through different root components of both the systems, AFS occupied more rooting volume. Total belowground sequestered Carbon was higher in AFS (59.2 kg tree-1) than FRS (54.7 kg tree-1). The pattern was similar in other components like fine roots, medium roots, coarse roots and stump roots. However, on hectare basis, FRS accumulated (11.1 Mg ha-1) more Carbon than AFS (8.2 Mg ha-1). Although FRS stored higher belowground Carbon (without grain production), AFS was more efficient on account of Carbon land equivalent ratio. Thus the two available management systems have their own advantages in terms of Carbon storage and grain production.
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