j.maleki

To investigate the effects of soil fertility methods on economic yield and essential oil compositions of Nigella sativa L., an experiment was conducted in a randomized complete block design with three replications. Experimental treatments included different levels of NPK chemical fertilizer, manure, NPK+ manure, and NPK+ manure+ inoculation of Azorizobium biofertilizer. Seed yield, aerial parts yield, and percentage, yield, and essential oil compounds were studied. The results showed that the highest seed yield (1270.43 kg.ha-1) was obtained in the 40 kg.ha-1 N+ 32 kg.ha-1 P+ 40 kg.ha-1 K+ 30 ton.ha-1 manure treatment. The highest percentage (0.25%) and essential oil yield (2.8 kg.ha-1) was obtained in the 40 kg.ha-1 N+ 32 kg.ha-1 P+ 40 kg.ha-1 K+ 30 ton.ha-1 manure+ Azurizobium treatment. The highest thymoquinone percentage (14.9%) was observed in the 30 ton.ha-1 manure treatment. Overall, the integrated and biological treatments had the most positive effects on seed yield and essential oil percentage of N. sativa. The use of suitable fertilizer sources not only increased the yield, essential oil percentage, and thymoquinone content in Nigella sativa, but also reduced the consequences of excessive use of chemical fertilizers. The use of integrated fertilization methods is an effective step to achieve the sustainable agriculture goals.

To investigate the effects of soil fertility methods on the quantitative yield and oil of medicinal plant black cumin (Nigella sativa L.), an experiment was conducted in a randomized complete blocks design with three replications. Experimental treatments included different levels of NPK chemical fertilizers, different levels of manure, combination of NPK+manure, and combination of NPK+manure with Azorhizobium biofertilizer inoculation. The results showed that plant nutrition increased plant height, plant dry weight, number of lateral branches, leaf area index, number of capsules per plant, number of seeds per capsule, grain yield, biological yield, relative leaf water content, and percentage and oil yield. The highest quantitative and qualitative characteristics were obtained in the chemical nutrition in the treatment of NPK: 120-96-120 (kg ha-1) and in the manure nutrition in the treatment of manure: 20 ton ha-1. In the chemical+manure combined method, the treatment of NPK: 40-32-40 (kg ha-1)+manure: 30 ton ha-1 was the best one. In the chemical+manure+biological combined method, the treatment of manure: 30 ton ha-1+ Azorhizobium+ NPK: 40-32-40 (kg ha-1) was observed as the most appropriate treatment. Overall, the combined treatment of NPK: 40-32-40 (kg ha-1) + manure: 30 ton ha-1+ Azorhizobium had the most positive effect on improving the biological yield and black cumin oil percentage, which also had the lowest amount of chemical fertilizer.

Deep excavations in soft clayey soils usually cause excessive ground settlement and wall movements due to the creep in soft soils. One of the commonly used methods for predicting these displacements is numerical analysis, however, in most cases for modeling soft clayey soils, soil behavior is considered to be time-independent. So, the effect of excavation time and creeping in soft soils are ignored. In this paper, the impact of the time of construction of the excavation and creep effect that occurs in soft soils are studied using three case studies. These three excavations are stabilized using a combination of soil anchorage and soil nailing methods. For studying the time influence and creep effect in soft soils with numerical modeling, excavations are modeled using three different soil constitutive models, namely Mohr-Coulomb, Hardening Soil (HS), and Soft Soil Creep (SSC) models. The real field records by installed in-situ instruments are employed to evaluate the performance of three constitutive models for simulating the excavation wall behavior. The obtained results show that for realistic simulation of the behavior of deep excavations, the construction time and the corresponding creeping behavior should be included in the numerical modeling procedure in order to better match the numerical predictions with the time-independent behavior of soft soils.