Important Soil Research Articles

First Report of Leaf Tip Necrosis of Camellia oleifera Caused by Nigrospora aurantiaca in China.

In recent years, Camellia oleifera C.Abel. has become one of the most important woody oil trees cultivated at a large scale in Guizhou Province, China. However, the leaf diseases limited the development of C. oleifera industry. In October 2023, typical symptoms of leaf tip necrosis were observed on leaves of C. oleifera (Changlin series) at a plantation in Dongfeng Forest Farm (109°10'28'E, 26°18'41'N), Liping County, with disease incidence of 30-40% (n=220) in the observed fields (30 m × 30 m). The brown lesion started from the leaf tips, gradually extended inward then turned gray-white, curled, withered and fell off, and the boundary between the diseased and healthy parts was obvious. Symptomatic leaves (n=20) were collected and surface disinfected with 2% NaClO for 30 s, rinsed three times in sterile distilled water, air-dried and placed on potato dextrose agar (PDA) medium and incubated at 25°C for 7 d. The fungal colonies of 6 isolates were initially white, with red pigment, and later gradually turned gray, eventually turning black. Conidia were globose to sub-globose, black, smooth, single-celled, discrete and solitary, measuring 5.1 µm±1.28×4.7 µm±1.24 (n=50). The morphological features of the isolates are similar to the description of Nigrospora (Wang et al. 2017). For molecular identification, DNA of the representative isolate LP1021 was extracted using a fungal genomic DNA extraction kit (Sangon, Shanghai, China). The rDNA internal transcribed spacer (ITS), translation elongation factor 1-α (TEF-1α) and β-tubulin (TUB2) were amplified with the primers ITS1/ITS4 (White et al.1990), EF1-728F/EF1-986R (Carbone and Kohn, 1999) and Bt2a/Bt2b (Glass and Donaldson, 1995). The sequences of ITS, TEF-1α and TUB2 were deposited in GenBank as accession numbers PP499217, PP529954, and PP529955, respectively. BLAST revealed that ITS, TEF-1a and TUB2 sequences showed 100%, 98.80% and 100% similarity to those of N. aurantiaca (NR153477.1, KY019295.1 and MK388225.1), respectively. The phylogenetic tree constructed with the software MEGA X using the Neighbor-Joining algorithm (Felsenstein, 1985) indicated the isolate LP1021 separated from N. chinensis previously reported from C. oleifera in China. Based on morphological and molecular characteristics, the fungal pathogen was identified as N. aurantiaca. A representative isolate LP1021 was deposited in the Forest Protection Laboratory, Guizhou University. To further confirm the pathogenicity, a conidial suspension (1×104 spores/mL) of the isolate LP1021 was sprayed on six pots of two-year-old healthy C. oleifera seedlings in vivo. The same amounts of seedlings were sprayed with distilled water as control. All plants were placed at a constant room temperature of 25 ± 2°C. After 15 d, the inoculated leaves showed typical symptoms, similar to those observed in the field, while the control remained healthy. The re-isolated fungal culture was identical to that originally obtained using the methods mentioned above, which fulfilled Koch's postulates. To the best of our knowledge, this is the first report of N. aurantiaca causing leaf tip necrosis of C. oleifera in China, which provides an important theoretical basis for the pathogen identification and scientific control strategies of leaf tip necrosis in C. oleifera.

A review on way towards mechanized castor cultivation

Castor (Ricinus communis L.) is an important non edible oil seed crop which is known for its oil content (48–60 percent) and it accounts for 0.15% of the global production of vegetable oil. In recent years, farmers have preferred castor cultivation due to its suitability for both rainfed and irrigated conditions. But the farmers face many challenges, which includes labour scarcity, pest incidence, high input and labour costs, inadequate market information, etc. Due to a significant labour shortage, the area under this crop is gradually decreasing. The high reliance on human labour which leads to the incompletion of various agronomic operations on time. In these circumstances, the cultivation of castor by adopting various mechanization techniques for critical operations such as field preparation, sowing, fertilizer application, weeding, irrigation, crop protection measures and harvesting will be the solution for getting higher productivity and profitability by spending minimum expenses. Adapting mechanization is crucial for achieving sustainable development goals by enhancing production through timely farm operations, minimizing losses and reducing operational costs through efficient management of expensive inputs.

Analysis of the Distribution Pattern of Asparagus in China Under Climate Change Based on a Parameter-Optimized MaxEnt Model

Asparagus (Asparagus officinalis L.) has high health and nutritional values, but the lack of scientific and rational cultivation planning has resulted in a decline in asparagus quality and yield. Important soil, climatic, anthropogenic, and topographic environmental factors influencing the distribution of asparagus cultivation were chosen for this study. The Kuenm package in the R language (v4.2.1) was employed to optimize the maximum entropy model (MaxEnt). Pearson’s correlation analysis, optimized MaxEnt, and geographic information spatial technology were then utilized to identify the main environmental factors that influence suitable habitats for asparagus in China. Potential distribution patterns, migration, and changes in trends concerning the suitability of asparagus in China under various historical and future climate scenarios were modeled and projected. Human activities and climate factors were found to be the primary environmental factors that influence the suitability distribution of asparagus cultivation in China, followed by soil and topographic factors. Historical suitable habitats covered 345.6 × 105 km2, accounting for 36% of China. These habitats are projected to expand considerably under future climatic conditions. This research offers a basis for the rational planning and sustainable development of asparagus cultivation.

Genetic Variation in a Crossing Population of Camellia oleifera Based on ddRAD Sequencing and Analysis of Association with Fruit Traits

Tea oil is an important high-quality edible oil derived from woody plants. Camellia oleifera is the largest and most widely planted oil-producing plant in the Camellia genus in China, and its seeds are the most important source for obtaining tea oil. In current research, improving the yield and quality of tea oil is the main goal of oil tea genetic breeding. The aim of this study was to investigate the degree of genetic variation in an early crossing population of C. oleifera and identify single nucleotide polymorphisms (SNPs) and genes significantly associated with fruit traits, which can provide a basis for marker-assisted selection and gene editing for achieving trait improvement in the future. In this study, we selected a crossing population of approximately 40-year-old C. oleifera with a total of 330 samples. Then, ddRAD sequencing was used for SNP calling and population genetic analysis, and association analysis was performed on fruit traits measured repeatedly for two consecutive years. The research results indicate that over 8 million high-quality SNPs have been identified, but the vast majority of SNPs occur in intergenic regions. The nucleotide polymorphism of this population is at a low level, and Tajima’s D values are mostly greater than 0, indicating that the change in this population was not suitable for the model of central evolution. The population structure analysis shows that the population has seven theoretical sources of genetic material and can be divided into seven groups, and the clustering analysis results support the population structure analysis results. Association analysis identified significant SNPs associated with genes related to the seed number of a single fruit and seed kernel oil content. Our findings provide a basis for molecular breeding and future genetic improvement of cultivated oil tea.

Significance of the GCC Countries in India’s Quest for Energy Security: Understanding the Trends and Challenges

The Gulf region has grown in importance as a strategic partner of India under Prime Minister Narendra Modi. This was brought to light in February 2024 when Modi visited the United Arab Emirates (UAE) and Qatar on his second last trip prior to India’s national elections in April-May 2024. The Gulf is now a top focus for foreign and security policy under Modi, and it is a crucial component of India's “extended neighbourhood,” where New Delhi has growing influence and interests. One of India's most important trading partners these days is the GCC (Gulf Cooperation Council). Overtaking the European Union, the area accounted for 15.8 percent of India’s overall trade in FY 2022–2023. At the centre of this partnership are Saudi Arabia and the United Arab Emirates (UAE), India's third and fourth-largest commercial partners, respectively. Saudi Arabia and Qatar have donated $3.2 billion and $1.5 billion, respectively, to India, while the United Arab Emirates has already invested $15.3 billion. Even if these investments show a strong economic alliance, the GCC and India have yet to finalise their 2022 proposal for a Free Trade Agreement (FTA). This progress has been halted by bureaucratic delays and differences among GCC member states. However, such a deal would be a significant step towards boosting bilateral trade and investment, especially as India looks to establish itself as a hub for investment and manufacturing in the face of changing global supply chains. The strategic alliance between India and the GCC nations is examined in this essay. India’s four-pronged energy security strategy-diversifying energy supplies, expanding India's exploration and production footprint, increasing the use of alternative energy sources, and addressing the energy transition through gas-based economies, green hydrogen, and electric vehicles-has helped the country navigate through the most difficult energy crisis the world has seen since the 1973 oil crisis. From 27 countries in 2006-07 to 39 in 2023-24, India expanded its crude oil supply base, adding new suppliers such as Columbia, Russia, Libya, Gabon, Equatorial Guinea, and others, while fortifying ties with nations like the US and Russia. However, the GCC countries continue to be India’s primary source of imports, accounting for over 65 percent of our total imports, despite India’s continuous efforts to diversify its economy and secure its growing energy needs from around the world. For this reason, energy plays a significant role in the relationship between India and the GCC countries. India’s steady availability to energy supply is essential to its fast economic expansion. India’s reliance on oil and hydrocarbon imports in general, which currently account for 37.5 percent of our total imports, would expand significantly in the future due to the country's growing use of fossil fuels, prompting it to look for more robust energy security. Thus, foreign diplomacy is an essential instrument for guaranteeing India’s energy security. As a result, energy security is now a key component of Indian foreign policy. This essay examines India’s energy security strategies, interests, and obstacles in the region. It also looks at how much India’s quest for energy security influences its policies in the Gulf. The role of the GCC nations in India’s pursuit of energy security is examined in this essay. The four literature reviews that form the basis of this paper are: an overview of India’s energy policy and Gulf region policy; the significance of energy cooperation with the GCC countries; India’s energy security challenges; and an assessment of the role of energy in India’s Gulf region policy.

Economic Analysis of the Impact of Some Trade Policies on Egypt's Imports of the Most Important Edible Oils

Economic Analysis of the Impact of Some Trade Policies on Egypt's Imports of the Most Important Edible Oils

Shear Wave Velocity Prediction with Hyperparameter Optimization

Shear wave velocity (Vs) is an important soil parameter to be known for earthquake-resistant structural design and an important parameter for determining the dynamic properties of soils such as modulus of elasticity and shear modulus. Different Vs measurement methods are available. However, these methods, which are costly and labor intensive, have led to the search for new methods for determining the Vs. This study aims to predict shear wave velocity (Vs (m/s)) using depth (m), cone resistance (qc) (MPa), sleeve friction (fs) (kPa), pore water pressure (u2) (kPa), N, and unit weight (kN/m3). Since shear wave velocity varies with depth, regression studies were performed at depths up to 30 m in this study. The dataset used in this study is an open-source dataset, and the soil data are from the Taipei Basin. This dataset was extracted, and a 494-line dataset was created. In this study, using HyperNetExplorer 2024V1, Vs prediction based on depth (m), cone resistance (qc) (MPa), shell friction (fs), pore water pressure (u2) (kPa), N, and unit weight (kN/m3) values could be performed with satisfactory results (R2 = 0.78, MSE = 596.43). Satisfactory results were obtained in this study, in which Explainable Artificial Intelligence (XAI) models were also used.

U.S. Foreign Policy in the Middle East: Strategic Goals, Oil Interests, and the Promotion of Democracy

This research explores the historical and contemporary role of U.S. intervention in the Middle East, with a particular focus on oil interests, political strategies, and regional stability. The study examines key agreements like the "fifty-fifty" profit-sharing deal in Saudi Arabia and the broader implications of U.S. involvement in Gulf politics. The strategic importance of oil to U.S. national security is a central theme, illustrating how energy concerns have shaped U.S. foreign policy in the region. A significant portion of the research delves into the tension between promoting democracy and securing U.S. strategic interests, highlighting the challenges faced in balancing these often conflicting goals. Methodologically, the research utilizes both quantitative and qualitative approaches, drawing on historical documents, diplomatic records, and contemporary analyses. The findings suggest that while the U.S. has made efforts to foster democratic reforms in the region, its interventions—such as the Iraq invasion—have often resulted in instability, sectarian violence, and the resurgence of authoritarian regimes. The research argues that the U.S. has maintained a strong presence in the Middle East primarily to safeguard its economic and security interests, understanding that the region is vital to both its energy supply and broader geopolitical strategy. The conclusion underscores that U.S. involvement in the Middle East will likely continue in the future, driven by the desire to secure energy resources, maintain regional influence, and counter rivals like Iran, China, and Russia. The research suggests that while U.S. efforts to promote democracy have been largely unsuccessful, its strategic interests will remain dominant in shaping its regional policies.

Harnessing Biochar for Sustainable Horticulture: Strategies to Cope with Abiotic Stress

Biochar, an important by-product of the waste biomass pyrolysis process, shows great potential to reduce the environmental impact of and address the serious problems related to climate change as well as to define an efficient circular economy model. Its use as a soil conditioner has increased the interest in biochar in agriculture over time. This review investigates how critical aspects such as starting material, temperature, and the presence or absence of oxygen during the pyrolysis process influence the yield and quality of this valuable soil conditioner. Considering the horticultural sector, this review also provides a comprehensive and detailed overview of how biochar positively influences growth, development, and yield by explaining the mechanisms and modes of action under both optimal growth conditions and unfavorable contexts (salt and water stress and the presence of heavy metals). The main mechanisms highlighted by this literature review are improvement in soil aeration and water-holding capacity, microbial activity, and nutritional status of soil and plants, as well as alterations in some important soil chemical properties. This in-depth review of the literature highlights how the interaction between biochar types, dose, crop species, and growing conditions (optimal or nonoptimal) result in nonunique responses. The heterogeneity of the results reported in the literature confirms how many of the topics discussed deserve further investigation, with particular attention to identifying the right dose of biochar in relation to the different preharvest factors considered.

Energy consumption forecasting for oil and coal in China based on hybrid deep learning

The consumption forecasting of oil and coal can help governments optimize and adjust energy strategies to ensure energy security in China. However, such forecasting is extremely challenging because it is influenced by many complex and uncertain factors. To fill this gap, we propose a hybrid deep learning approach for consumption forecasting of oil and coal in China. It consists of three parts, i.e., feature engineering, model building, and model integration. First, feature engineering is to distinguish the different correlations between targeted indicators and various features. Second, model building is to build five typical deep learning models with different characteristics to forecast targeted indicators. Third, model integration is to ensemble the built five models with a tailored, self-adaptive weighting strategy. As such, our approach enjoys all the merits of the five deep learning models (they have different learning structures and temporal constraints to diversify them for ensembling), making it able to comprehensively capture all the characteristics of different indicators to achieve accurate forecasting. To evaluate the proposed approach, we collected the real 880 pieces of data with 39 factors regarding the energy consumption of China ranging from 1999 to 2021. By conducting extensive experiments on the collected datasets, we have identified the optimal features for four targeted indicators (i.e., import of oil, production of oil, import of coal, and production of coal), respectively. Besides, we have demonstrated that our approach is significantly more accurate than the state-of-the-art forecasting competitors.

Analysis of the Genomes and Adaptive Traits of Skermanella cutis sp. nov., a Human Skin Isolate, and the Type Strains Skermanella rosea and Skermanella mucosa.

The genus Skermanella comprises important soil bacteria that are often associated with the crop rhizospheres, but its physiological traits remain poorly understood. This study characterizes Skermanella sp. TT6T, isolated from human skin, with a focus on its metabolic and environmental adaptations. Genome sequencing and phylogenomic analyses revealed that the strain TT6T is most closely related to S. rosea M1T, with average nucleotide identity and digital DNA-DNA hybridization values of 94.14% (±0.5%) and 64.7%, respectively. Comparative genomic analysis showed that the strains TT6T, S. rosea M1T and S. mucosa 8-14-6T share the Calvin cycle, and possess photosynthetic genes associated with the purple bacteria-type photosystem II. The strains TT6T and S. rosea M1T exhibited growth in a nitrogen-free medium under microaerobic conditions, which were generated in test tubes containing 0.1% soft agar. Under these conditions, with nitrate as a nitrogen source, S. rosea M1T formed gases, indicating denitrification. Strain TT6T also contains gene clusters involved in trehalose and carotenoid biosynthesis, along with salt-dependent colony morphology changes, highlighting its adaptive versatility. Genomic analyses further identified pathways related to hydrogenase and sulfur oxidation. Phenotypic and chemotaxonomic traits of strain TT6T were also compared with closely related type strains, confirming its genotypic and phenotypic distinctiveness. The new species, Skermanella cutis sp. nov., is proposed, with TT6T (=KCTC 82306T = JCM 34945T) as the type strain. This study underscores the agricultural and ecological significance of the genus Skermanella.

Partial replacement by ammonium nutrition enhances Brassica napus growth by promoting root development, photosynthesis, and nitrogen metabolism.

Nitrogen (N) is crucial for plant growth, available primarily as nitrate (NO3-) and ammonium (NH4+). However, its presence in soil is often limited, necessitating strategies to augment N availability. This study delves into the enigmatic interplay between NO3- and NH4+ in fostering the growth of Brassica napus, an important oil crop worldwide. Here, we examined the growth responses of 49 B. napus varieties to five NH4+:NO3- ratios (12:0, 9:3, 3:9, 1:11, 0:12). In general, the biomass of 49 rapeseed varieties increased with the decrease of NH4+ to NO3- ratios in the growth environment. However, different varieties may respond diversely to the mixed N sources, or sole NO3- or NH4+ condition. For some cultivars, the mixed N supply significantly enhanced the plant growth compared with the sole NO3- conditions. Thus, we further investigate the morphological, physiological and molecular response of rapeseed to the mixed N source condition using sole NO3- as a control. The results show that partial replacement by ammonium nutrition in the environment can promote rapeseed root development, net photosynthetic rate and NO3- reduction compared to NO3--only conditions. Using transcriptome analysis, we found a total of 399 and 465 genes which were differentially expressed in root and shoot under A1N11 compared to A0N12 treatments, respectively. Genes involved in photosynthesis, N uptake and assimilation were upregulated by mixed N supplies. These findings highlight that the mixed N supply primarily stimulates B. napus growth by enhancing root development, photosynthesis and N metabolism in the shoot. Such insights are crucial for optimizing N form selection in B. napus to enhance plant performance and N use efficiency.

Measuring WTO Approaches in Resolving Palm Oil and Biofuel Trade Disputes from Indonesia

<div><table cellspacing="0" cellpadding="0" align="left"><tbody><tr><td align="left" valign="top"><p>Indonesia is the world's leading producer of palm oil, with significant exports to European Union member states. However, the EU has recently imposed stricter limitations on palm oil imports, particularly from Indonesia, through policies such as the Renewable Energy Directive (RED) and RED II. This article examines the measures imposed by the WTO to address this trade dispute. Using a doctrinal approach, the study collects data from primary legal sources, such as laws, regulations, and court decisions, as well as secondary sources, including journals and books. The findings reveal that Indonesia's request for negotiations with the EU was rejected, prompting the WTO to establish a panel. However, the panel's decision lacks legal force until the appeal process is concluded. The situation is further complicated by the Appellate Body's inability to function due to the United States’ deliberate refusal to approve new appointments, leaving the dispute unresolved. Consequently, the WTO Dispute Settlement Body's ruling lacks legal certainty, raising the potential for a trade war between Indonesia and the EU. This research underscores the need for effective dispute resolution mechanisms within the WTO to address such critical trade issues.</p></td></tr></tbody></table></div>

Policy Making for Oil Imports by United Nations’ Countries Using Multi-Objective Mixed Integer Linear Programming

Policy Making for Oil Imports by United Nations’ Countries Using Multi-Objective Mixed Integer Linear Programming

Oil spill cleanup using EDTA-coated magnetite magnetic nanoparticles

As a result of the critical importance of crude oil in modern industrial society, oil spills, specifically those involving crude oil, generate substantial environmental and ecological difficulties. In contrast to conventional treatment approaches, nanotechnology has demonstrated its efficacy in remedying oil spills This type of pollution could occur during oil investigation, transit, or storage. This study adopted a straightforward and economical method utilizing iron oxide magnetic nanoparticles for oil spills cleanup. Magnetite Fe3O4 MNPs were synthesized using the co-precipitation technique, which involved combining ferric and ferrous ions in an alkaline solution at 80°C and a pH of 14. MNPs were characterized using X-ray diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and vibrating sample magnetometer (VSM). To improve their stability and efficacy, MNPs were coated with ethylenediaminetetraacetic acid (EDTA). Three samples of crude oil with different APIs (23, 28.4, and 40.3) were used to study the ability of coated MNPs for oil spill cleanup. Removal experiments were conducted at 25°C with a mass range of adsorbent (0.02-0.06 g). A neodymium magnet was utilized to extract the oil-contaminated magnetic nanoparticles from the water. The gravimetric oil removal (GOR) for APIs 23, 28.4, and 40.3 were 11.4 - 3.35, 7.19- 2.15, and 4.81 to 1.16 g/g, respectively. Experimental results demonstrated an inverse relationship between GOR and the API value, indicating that as the API value decreased, GOR increased, and vice versa. Furthermore, as the mass of the adsorbent material increased (0.02-0.06g), the GOR value decreased.

Comparing the Efficacy of Single and Multiple Visits by Honey and Solitary Bees on Sunflower Seed Production

Sunflower (Helianthus annuus L.) is an important oil seed crop with a considerable acreage of cultivated hybrids in Pakistan. Sunflower crops depend on insect pollination for seed setting, as it attracts diverse pollinator fauna, mainly due to pollen and nectar availability. This study was conducted in the agricultural landscape of Multan, Pakistan, to evaluate the role of native and social bees in sunflower seed production. The abundance and diversity of pollinators were assessed. Effectiveness was tested regarding foraging behavior, including visitation rate, stay time, and seed set efficacy for single and multiple visits (5, 10, 15). Additionally, various reproductive success parameters were recorded: flower head (pseudanthium) diameter, flower head weight, seed weight/flower head, and number of seed/flower head. The results showed that the relative abundance of honey bees was the highest (77%) in both years, followed by solitary bees (17%), while syrphid flies were the least abundant (6%) on sunflower. Among honey bees, Apis mellifera and A. dorsata were the most abundant in both years, followed by the solitary bee Xylocopa sp. Furthermore, in single and multiple seed set efficacy (5 and 10 visits), the solitary bee Xylocopa sp. produced the maximum seeds, followed by A. mellifera. Higher seed production could be achieved with a focused conservation plan of solitary and managed bees on sunflower.

Genome-Wide Identification, Conservation, and Expression Pattern Analyses of the BBR-BPC Gene Family Under Abiotic Stress in Brassica napus L.

The BBR-BPC gene family is a relatively conservative group of transcription factors, playing a key role in plant morphogenesis, organ development, and responses to abiotic stress. Brassica napus L. (B. napus), commonly known as oilseed rape, is an allopolyploid plant formed by the hybridization and polyploidization of Brassica rapa L. (B. rapa) and Brassica oleracea L. (B. oleracea), and is one of the most important oil crops. However, little is known about the characteristics, conservation, and expression patterns of this gene family in B. napus, especially under abiotic stress. To explore the characteristics and potential biological roles of the BBR-BPC gene family members in B. napus, we conducted identification based on bioinformatics and comparative genomics methods. We further analyzed the expression patterns through RNA-seq and qRT-PCR. We identified 25 BBR-BPC members, which were classified into three subfamilies based on phylogenetic analysis, and found them to be highly conserved in both monocots and dicots. The conserved motifs revealed that most members contained Motif 1, Motif 2, Motif 4, and Motif 8. After whole-genome duplication (WGD), collinearity analysis showed that BBR-BPC genes underwent significant purifying selection. The promoters of most BBR-BPC genes contained cis-acting elements related to light response, hormone induction, and stress response. RNA-seq and qRT-PCR further indicated that BnBBR-BPC7, BnBBR-BPC15, BnBBR-BPC20, and BnBBR-BPC25 might be key members of this family. This study provides a theoretical foundation for understanding the potential biological functions and roles of the BBR-BPC gene family, laying the groundwork for resistance breeding in B. napus.

Physical and chemical soil characterises integrating with GIS technique and regression models to optimize landfill location for various hospitals in Kirkuk city, Iraq

Leachate infiltration into groundwater is a major contributor to groundwater pollution, posing health hazards to neighbouring communities. Thus, this study aims to utilize Geographic Information System (GIS) procedure incorporated with regression models to assess soil characteristics and evaluate soil plasticity index as an indicator for landfill construction, specifically for medical and industrial refuse. Particularly, soil samples were collected from three different public hospitals within Kirkuk city, Iraq to optimize the best site for landfill construction. The research has focused on creating digital maps and analysing various collected physical and chemical soil characteristics. In addition, single linear regression model has been employed to evaluate the soil plasticity index in terms of individual physical and chemical soil properties. Furthermore, multi-linear regression model was applied to compute soil plasticity index benefiting from individual and combined physical and chemical soil characteristics. Precise associations between PI (plasticity index) and soil properties are determined, making it possible to indirectly quantify important soil swelling characteristics with low expense and effort to be used for optimizing landfill location. Moreover, using multi-linear regression consideration, various equations are analysed, demonstrating encouraging outcomes in predicting PI values with multiple R values ranging from 0.510 to 0.689. These models illustrate the benefit of including both physical and chemical soil properties to enhance the accuracy of PI estimation to give the chance for optimizing the landfill location depending on accessible individual or combined chemical and physical soil properties.

Simulation of Flax Threshing Process by Different Forms of Threshing Drums in Combined Harvesting

Flax, an important oil and fiber crop, is widely cultivated in temperate and sub-frigid regions worldwide. China is one of the major producers of flax, with Gansu Province predominantly practicing cultivation in hilly areas. However, common issues such as feeding difficulties, stem entanglement, and low threshing efficiency significantly restrict the improvement of planting efficiency. This study addresses the key technical challenges in flax combine harvesting in hilly regions by developing a discrete element model of the flax plant and utilizing DEM-FEA co-simulation technology. The performance of two threshing drum models (T1 and T2) was analyzed, focusing on motion trajectory, stress distribution, and threshing effects. The simulation results show that the T2 model, with its combination of rib and rod tooth design, significantly improves threshing and separation efficiency. The loss rate was reduced from 5.6% in the T1 model to 1.78% in the T2 model, while the maximum stress and deformation were significantly lower, indicating higher structural stability and durability. Field validation results revealed that the T1 model had a total loss rate of 3.32%, an impurity rate of 3.57%, and an efficiency of 0.09 hm2/h. In contrast, the T2 model achieved a total loss rate of 2.29%, an impurity rate of 3.39%, and an efficiency of 0.22 hm2/h, representing a 144.4% improvement in working efficiency. These findings indicate that the T2 model has a higher potential for flax harvesting in hilly and mountainous regions, especially in improving threshing efficiency and operational stability, providing an important theoretical basis for optimizing threshing equipment design.

Physicochemical Characterization of Cucurbita pepo L. (Cucurbitaceae) Seed Oil Obtained by Cold Organic Extraction

Background: African flora is full of many plant species used by populations for a long time as sources of food, timber, energy and remedies for various somatic or spiritual ailments. In tropical areas, there are many sources of vegetable oils available, but not exploited or not used optimally. Oilseeds are important sources of oils of food, industrial and pharmaceutical importance. Aim: The aim was carry out to determine some of the physicochemical characteristics of Cucurbita pepo seeds oil in order to promote its valorization. Results: After extraction of the oil by cyclohexane, we obtained a yield of 31.26 %. The study of physical parameters indicate that the oil is pure and belongs to the group of non-drying oils with values of 0.915 ± 0.01 and 1.468 ± 0.01 for density and refractive index respectively. This is confirmed by the results of chemical parameters study. Indeed the low values of the acid and peroxide index (respectively 0.41 ± 0.13 mg KOH/g oil and 8.92 ± 1.08 mEq O2 / kg oil) confirm the stability of the oil, which allows it to better resist oxidation. The value of the iodine index (88.15 ± 2.57 g iodine /100 g oil) shows that the oil is of the oleic type. The high value of the saponification index (191.67 ± 1.52 mg KOH/g) oil proves that the oil has long carbon chains. Conclusion: Based on these results, Cucurbita pepo seeds oil would be a good candidate in the food industry, phytomedicine and for the formulation of cosmetic or body care products.