The Impact of Nitrogen on the Yield Formation of Artemisia dubia Wall: Efficiency and Assessment of Energy Parameters

Abstract

With the increasing importance of energy crops, research on potential energy crops is carried out to identify plant species with high productivity and energy value. The field experiment with the new promising energy crop, Artemisia dubia (wormwood), was executed at the Vėžaičiai Branch of the LAMMC. The soil site was naturally acidic Retisol (pH 4.2–4.4). The species was investigated as an energy crop through the evaluation of its biomass productivity and some energetical qualities. According to the three investigation years, DM yield significantly varied depending on the growing season, cutting time and nitrogen rate. The highest average DM yield was observed in 2020—10.58 t ha−1. On average, the DM yield varied from 6.49 t ha−1 (first cutting) to 11.82 t ha−1 (third cutting). The DM yield was positively correlated with stem height and the mass of one stem. Nitrogen use efficiency (NUE) depended on the growing season, cutting time and nitrogen rate. Both N90 and N180 rates should be used for A. dubia fertilization. Energy growing analysis (including direct and indirect expenses) revealed that the highest share of energy expenses are due to indirect energy expenses (particularly nitrogen application). EUE (energy utilization efficiency) tends to decrease as a result of increasing nitrogen fertilization. Overall, A. dubia granules are characterized by a high calorific value.

Evaluation of the Productivity and Potential Utilization of Artemisia dubia Plant Biomass for Energy Conversion

“…When evaluating the use of nitrogen fertilizers (N180), the calorific value of A. dubia was slightly lower. When evaluating the amount of nitrogen in the grown biomass, it was found that when nitrogen fertilizers were used, the amounts for Artemisia dubia biomass were higher than for the biomass grown in unfertilized soil [ 24 ].…”

“…These experiments were performed in the Thermal Equipment Research and Testing Laboratory of the Lithuanian Energy Institute (LEI). Based on standard methodologies, the lower and higher heating values (LHVs and HHVs) of the pellets, the values of chlorine and other elements, and the amount of ash after pellet burning were determined [ 24 ].…”

“…In this respect, there are many sites that are not suitable for traditional agricultural crops here. Viewed from the other side, to not compete with traditional food crops, different alternative non-food crops or energy crops might be grown on the land which is less suitable or unprofitable as traditional farming land [ 24 ]. For that reason, plantations for a sufficient new sort of A. dubia plant which grows well in these lands and without the use of fertilizers were established.…”

Factors Influencing Artemisia Dubia Plant Biomass Productivity and Evaluation of Technological, Power and Environmental Parameters of Plant Utilization for Energy Conversion

“…Factor 2 was nitrogen rates. The seedlings were planted and fertilized by 3 nitrogen levels (0, 90 and 180 N kg ha -1 ) [24]. However, this article presented only two experiments, when nitrogen levels were 0 and the highest amount was 180 kg ha -1 .…”

“…In this respect, there are many sites that are not suitable for traditional agricultural crops here. Viewed from the other side, to not compete with traditional food crops, different alternative non-food crops or energy crops might be grown in the land which is less suitable or unprofitable for traditional farming land [24].…”