How planting density and grazing intensity affect the above- and below-ground carbon pools in a dryland ecosystem?

Climate change is known as one of the most important environmental challenges. Sequestration of carbon in terrestrial ecosystems is a low-cost option that may be available in the near-term to mitigate increasing atmospheric CO۲ concentrations, while providing additional benefits. In this study, we estimated the effects of planting density and grazing intensity on the potential of Atriplex canescens for carbon sequestration in a rangeland in Qazvin Province, Iran. The experimental design consisted of a randomized block design, including two planting densities (۲ × ۲m and ۴ × ۴m) and four grazing intensity treatments simulated by different plant pruning intensities. We observed no significant difference between the rate (%) of organic carbon in the treatments of density, grazing intensity, and their interaction in the ۰-۳۰cm and ۳۰-۸۰cm soil layers. Between the treatments of height pruning, control (no pruning) and light grazing, had the highest total biomass and total carbon. The total biomass carbon content of ۲۳۷۰ kg m-۲ in the ۲×۲m treatment was about twice as much that of ۴x۴m treatment. These findings can be useful in rangeland management plans.

Keywords:

Carbon sequestration , Biomass , Atriplex canescens , Grazing intensity , Planting density