Evaluation and Zoning of Carbon Sequestration Potential in Canola Plant Organs (Brassica napus L.) (Case study: Sorkhankalateh region, Gorgan County)

Carbon sequestration is the ability of plant biomass and the soil to absorb atmospheric carbon dioxide and store it for a long time. Therefore, carbon sequestration occurs when the rate of absorption of carbon dioxide by plants from the atmosphere, is larger than the total soil respiration rate, plant respiration and plant biomass cut (Anderson et al., 2008). Today, agriculture is effective in carbon sequestration through as an important factor in in order to mitigate the effects of climate change. In the past, carbon sequesters are mainly raised in relation to forests. But today, crops production or animal husbandry can also be effective by maintaining plant residues and proper consumption of organic fertilizers obtained in soil in carbon sequestration (Seyedi, 2016). Therefore, this study was conducted in order to evaluation the carbon sequestration potential in canola plant tissues in agroecosystems Sorkhankalateh region, Gorgan county.

This study was conducted to evaluation the carbon sequestration potential in above- ground and below ground tissues of canola (Brassica napus L.) in agricultural lands of Sorkhankalateh region (Gorgan County) during 2021-2022. In this study, 50 canola fields were selected and sampling from the fields based on the W pattern in the four geographical directions of the region. An electric burn furnace method was used to determine the conversion coefficients of carbon sequestration potential in above- ground and below ground tissues (including siliques, seeds, stems, leaves and roots). As well as, the ratio of above- ground to below ground tissues and harvest index were estimated to determine the net primary production based on carbon content in the above ground tissue, below ground and total plant, and the carbon allocation coefficients in each of the canola plant organs. Finally, using the ArcGIS software version 10.3, the amount of carbon sequestration potential in each of the canola organs was presented in the form of a map, and all the data used were analyzed using SAS software version 9.3.Results and DiscussionBased on the findings of this study, the average deposited carbon in total plant tissues in under cultivated fields of Hayola 50 cultivar was equal to 6657.47 kg per hectare and in under cultivated fields of Trapper cultivar equal to 6560.33 kg per hectare. So that the average carbon sequestration potential was obtained in the stem in two Hayola 50 and Trapper cultivars equal to 2012.36 and 1993.97, in seed 1717.20 and 1639.95, in pod 1676.77 and 1608.36, in leaf 602.90 and 615.72, and in root 648.21 and 703.30 kg per hectare, respectively. Also, the shares amount of the allocation coefficient of each of the economic tissues, stem, leaf and silique, root and root secretions were obtained, in two Hayola 50 and Trapper cultivars equal to 21.17 and 20.42, 63.60 and 63.49, 9.22 and 9.74, and 5.99 and 6.33 percent, respectively. In this study, the average total carbon sequestation potential in above- ground and below ground tissues was equal to 6610.86 kg per hectare. The highest and lowest carbon sequestation potential was obtained for stem with 2081.35 kg per hectare and leaf with 759.89 kg per hectare, respectively. Also, in the survey of carbon sequestration in above- ground and below ground tissues in canola fields, it was determined that there was a significant difference in 99% level. The results of carbon sequestration maps showed that there was the highest carbon sequestration rate in the fields located in the west and northwest, and carbon sequestration rate was lower in the fields located in the southern and eastern regions.