Soil Resources Research Articles

Microbe–plant–nanoparticle interactions: role in bioremediation of petroleum hydrocarbons

ABSTRACT Petroleum hydrocarbons (PHCs) are organic substances that occur naturally on earth. PHCs have emerged as one of the most prevalent and detrimental contaminants in regions comprising soil and water resources. The limitations of conventional physicochemical and biological remediation solutions could be solved by combining remediation techniques. An effective, affordable, and environmentally benign method of reducing petroleum toxins is provided by the advanced idea of bioremediation, which has evolved into nanobioremediation. Environments contaminated with PHCs have been restored through microbe–plant–nanoparticle (NP)-mediated remediation, this review emphasizes how various metallic NPs interact with microbes and plants changing both their activity and that of enzymes, therefore accelerating the remediation process. This work further examines the challenges and possible uses of nanobioremediation, as well as the application of novel technologies in the interactions between bacteria, plants, and NPs for the bioremediation of PHCs. Furthermore, it has been shown that the use of plant-based, microbe-based, microbe–plant-based, and microbe–plant–NP-based techniques to remediate contaminated soils or water bodies is economical and environmentally beneficial. Microbial consortia have been reported as the treasure houses for the cleaning and recovery of hydrocarbon-contaminated environments, and the development of technologies for bioremediation requires an understanding of hydrocarbon degradation mechanisms.

Research Progress and Prospects of Oil Saturation Evaluation Methods in Shale Oil Reservoirs

The core of the exploration and development of unconventional oil and gas resources, such as shale oil, lies in the effective identification and scale utilization of the sweet spot. Oil saturation is an important parameter in evaluating the sweet spot. Aiming to solve the many current problems of oil saturation logging evaluations of shale oil reservoirs, this study outlines the research progress of oil saturation logging evaluations of shale oil from the three aspects, namely, the electrical method, non-electrical method, and machine learning, through researching the literature and practical applications. At the same time, several typical saturation models are applied to shale oil reservoirs in the Qingshankou Formation of the Gulong Depression, and applicability analyses are conducted. Lastly, the advantages and disadvantages of each oil saturation calculation model are summarized, and suggestions are given for conducting research using each type of method. This study has certain significance in the selection of oil saturation logging evaluation methods for shale oil reservoirs and provides directions for improvement.

Beneath the surface: assessing pollution levels near major solid waste dumpsites in Lagos, Nigeria.

Effective solid waste management is a critical environmental challenge, particularly in rapidly growing Global South countries like Nigeria. This issue is exacerbated by burgeoning populations, lax waste regulations, and the widespread practice of open dumping. The deterioration of soil quality and alteration of water quality are major consequences of open waste dumping, posing significant environmental and public health risks. This study aims to assess the environmental risk and pollution status of soil and water resources near major dumpsites in Lagos. It aims to offer insights that can inform targeted interventions and policy measures not only in Lagos but also in comparable urban settings worldwide. Results indicated that important soil parameters, including TN (11.89-13.83mg/kg), pH (6.45-7.35), sulfate (36.71-39.49mg/kg), phosphate (9.31-14.39mg/kg), and electrical conductivity (342-566 µS/cm), were significantly affected by the dumpsites. Additionally, concentrations of heavy metals varied, with some exceeding permissible limits set by international standards, highlighting the environmental challenges posed by improper waste disposal in urban settings like Lagos. The analyzed parameters for water were mostly within acceptable limits, indicating a lesser impact of the waste dump on water resources. Water samples from boreholes and hand-dug wells near three dumpsites showed that pH, TDS, and heavy metal concentrations were mostly within WHO limits, with borehole water deemed safe for drinking and hand-dug wells suitable for cleaning. To alleviate the environmental impacts of open dumpsites, it is recommended to implement effective waste segregation, recycling programs, controlled landfilling, and investment in waste treatment technologies, along with regular water quality monitoring to prevent further pollution and protect public health. While these measures offer opportunities, they also face significant challenges due to financial and land constraints. Therefore, strong public awareness, infrastructure investment, and government commitment are essential, along with coordinated efforts among the government, private sector, and communities.

Practical approach for sand-shale mixtures classification based on rocks multi-physical properties

Sandstones are the most common reservoir rocks, providing reservoirs for oil and gas and serving as reservoirs for groundwater. The Gulf of Mexico is known for its sand-shale mixtures and potential for its oil and hydrate gas resources in sandstone units. Understanding these variations is essential for assessing hydrocarbon potential and unconventional prospectivity. In this study, we utilized the Elastic, Electrical, and Radioactive (EER) properties of rocks for lithological categorization of well logging data, leading to the development of a novel rock physics template. The electrical and radioactive properties of the rocks facilitated a broad lithological classification, while their elastic characteristics helped distinguish between porous and low-porosity zones. Electrical and radioactive properties are utilized for well data classification because in sandstone formations, there is a decrease in log gamma and an increase in log resistivity. As a result, these opposing shifts in the two geophysical logs enhance the spread of data points on the lithological resistivity-gamma ray scatter plot, thereby simplifying the process of lithological categorization. Ultimately, the well logging data was sorted into three distinct categories: low shale sands (shale volume < 30 %), sand-shale mixtures (shale volume = 30 to 80 %), and shale-dominated areas. Subsequently, the Thomas Stieber model was employed to identify the types of clay minerals present in both sandstones and sand-shale mixtures. The model's findings revealed that dispersed type clay minerals are predominantly found in sandstones, with laminar and structured types being relatively rare. However, in sand-shale mixtures, both dispersed and laminar clays observed.

Petroleum Engineering Research Shifts Focus From Oil and Gas to New Horizons

Undergraduate education in petroleum engineering (PE) has survived the latest downturn in the industry, and enrollment has started to show an uptick in numbers. However, a different trend is evident in graduate training and academic research: the number of researchers being trained in oil and gas topics is drastically dropping. The story can be summarized in Fig. 1. Funding trends in PE departments have been shifting away from oil and gas research. These shifts require large investments in skill-building, expertise, and laboratory infrastructure, which makes it much harder to reverse the trend. Consequently, the shift may permanently alter the identity of PE departments, something that will not impact only graduate education but could alter the overall identity of these departments and the workforce they train. The data shared in Fig. 1c shows that more than 50% of the 2023 research awards, which will fund graduate students earning degrees between 2025 and 2026, are going to be invested in geothermal, carbon management, hydrogen, emissions, and other topics that do not support improving oil and gas resource extraction. While 73% of the 2023 MSc and PhD graduates still studied oil and gas topics around reservoir, production, fracturing, and drilling, as shown in Fig. 1a, this number is expected to drop to under 50% for 2026 graduates. Fig. 1b reveals the accelerated trend of this transition, where only 65% of the publications generated from these departments in 2023 covered oil and gas topics. Under 60% of the 2024 and 2025 graduates who published in 2023 are building expertise in oil and gas research and development. The team collected data to study the trends over the past 10 years. It included over $137 million in external research funding and over 1,900 thesis/dissertations, in addition to over 1,100 publications in 2023. More details about these numbers can be found in SPE 220735. The trends in graduate training and research funding over the past 10 years are shown in Fig. 2, where the axis for graduate training is shifted by 3 years to account for the lag between the date funding was received and the graduation date for the students it supported. When looking at numbers rather than percentages (Fig. 3), oil and gas research funding to four of the major PE departments in the US dropped from $30 million in 2014 to under $10 million in 2023 as shown in Fig. 3a. Funding in these departments now hovers at around $20 million, where the gap was filled by transitioning to the study of sustainable geoenergy topics relating to carbon and hydrogen storage and the extraction of geothermal energy, as shown in Fig. 3b.

Different mechanisms of two oil-soluble additives to reduce heavy crude oil viscosity

The depletion of light crude oil resources necessitates the efficient development of heavy crude oil, characterized by high density and viscosity. In this work, we used molecular dynamics (MD) simulations to investigate the mechanisms by which two oil-soluble viscosity reducers (VRs) reduce the viscosity of heavy crude oil. Our results reveal that direct interaction between VRs and asphaltene (ASP) aggregates is not the sole pathway for viscosity reduction. Instead, targeting resin (RES) emerges as a critical strategy. The first kind of VR (VR1), with its polar acrylamide head, binds effectively to ASP, reducing the exposure of ASP to other heavy oil components and thereby decreasing the friction between ASP and these components. In contrast, the second kind of VR (VR2), with a maleic anhydride head, tends to disperse away from ASP aggregates, reducing viscosity by weakening the intermolecular interactions between RES and lighter components. These findings elucidate distinct mechanisms by which VRs mitigate the viscosity of heavy crude oil and provide insights for the design of more effective oil-soluble VRs for future heavy oil exploitation.

Innovations in residue upgrading for the Niger delta by transforming heavy oil fractions into high-value products: A state of the art review

This review discusses new innovations in residue upgrading technologies for the conversion of heavy oil fractions into high-value products, especially for Delta and Rivers States of the Niger Delta region. Recent works within the 2020-2024 period show that upgrading methods have been significantly developed; however, no prior work has been done regarding applying those upgrading techniques to the peculiar nature of crude oil from this region. The paper probes the environmental impacts of these technologies, emphasizing the need for localized assessment that would take into consideration the fragile ecosystems of Delta and Rivers States. It further assesses the economic viability of scaling up the implementation of advanced upgrading processes within the current refining infrastructure. The discussion covers variable quality heavy oil in these regions and what that does to upgrading efficiency, how to integrate these technologies into the current refining practices, underlines the potential socio-economic advantages for the local communities through the creation of jobs and enhancing the skills of those communities to underscore the importance of these innovations for sustainable development. The review establishes that in such siamese twin areas, further research is needed to ensure that heavy oil resources in Delta and Rivers States are utilized effectively while ensuring that there is a minimal environmental impact from the extraction process.

Evaluation and Optimization of Cement Slurry Systems for Ultra-Deep Well Cementing at 220 °C

With the depletion of shallow oil and gas resources, wells are being drilled to deeper and deeper depths to find new hydrocarbon reserves. This study presents the selection and optimization process of the cement slurries to be used for the deepest well ever drilled in China, with a planned vertical depth of 11,100 m. The bottomhole circulating and static temperatures of the well were estimated to be 210 °C and 220 °C, respectively, while the bottomhole pressure was estimated to be 130 MPa. Laboratory tests simulating the bottomhole conditions were conducted to evaluate and compare the slurry formulations supplied by four different service providers. Test results indicated that the inappropriate use of a stirred fluid loss testing apparatus could lead to overdesign of the fluid loss properties of the cement slurry, which could, in turn, lead to abnormal gelation of the cement slurry during thickening time tests. The initial formulation given by different service providers could meet most of the design requirements, except for the long-term strength stability. The combined addition of crystalline silica and a reactive aluminum-bearing compound to oil well cement is critical for preventing microstructure coarsening and strength retrogression at 220 °C. Two of the finally optimized cement slurry formulations had thickening times more than 4 h, API fluid loss values less than 50 mL, sedimentation stability better than 0.02 g/cm3, and compressive strengths higher than 30 MPa during the curing period from 1 d to 30 d.

Temperate Soils Exposed to Drought—Key Processes, Impacts, Indicators, and Unknowns

The summer drought in the United Kingdom (UK) in 2022 produced significant speculation concerning how its termination may impact and interact with the soil resource. Whilst knowledge regarding soils and droughts exists in the scientific literature, a coherent understanding of the wider range of impacts on soil properties and functions has not been compiled for temperate soils. Here, we draw together knowledge from studies in the UK and other temperate countries to understand how soils respond to drought, and importantly what and where our knowledge gaps are. First, we define the different types of droughts and their frequency in the UK and provide a brief overview on the likely societal impacts that droughts place on the soil and related ecosystems. Our focus is on ‘agricultural and ecosystem drought’, as this is when soils experience dry periods affecting crops and ecosystem function, followed by rewetting. The behaviour of moisture in soils and the key processes that contribute to its storage and transport are examined. The principal changes in the physical, chemical, and biological properties of soils resulting from drought, and rewetting (i.e., drought termination) are discussed and their extensive interactions are demonstrated. Processes that are involved in the rewetting of soils are explored for soil and catchment-scale soil responses. Lastly, soils’ recovery after drought is considered, knowledge gaps are identified, and areas to improve understanding are highlighted.

Including soil spatial neighbor information for digital soil mapping

Digital soil mapping (DSM) is transforming how we understand and manage soil resources, offering high-resolution spatial–temporal soil information essential for addressing environmental challenges. The integration of environmental covariates has advanced soil mapping accuracy, while the potential of neighboring soil sample data has been largely overlooked. This study introduces soil spatial neighbor information (SSNI) as a novel approach to enhance the predictive power of spatial models. Utilizing two open-access datasets from LUCAS Soil and Meuse, our findings showed that incorporating SSNI improved the accuracy of random forest models in mapping soil organic carbon density (reduced %RMSE of 3.1%), cadmium (reduced %RMSE of 3.6%), copper (reduced %RMSE of 5.9%), lead (reduced %RMSE of 11.5%), and zinc (reduced %RMSE of 7.4%). Compared to the inclusion of buffer distance or oblique geographic coordinates for modelling, SSNI also performed better for both LUCAS Soil and Meuse datasets. This study underscores the value of SSNI in improving digital soil maps by capturing the neighboring information. Embracing SSNI could lead to more informed decision-making in soil management and its potential applicability across other disciplines also remains open for exploration in future research endeavors.

Structural response and damage assessment method for subsea pipe-in-pipe subjected to anchor impact

The pipe-in-pipe system is widely used in the development and transportation of offshore oil and gas resources. The damage caused by anchor impacts on the pipe-in-pipe system has long been a focal point and challenge in both engineering and academic fields. Numerical simulation method is employed to investigate the impact process of anchors on pipe-in-pipe systems, revealing the variation patterns of pipeline deformation response over time. The structural response of the pipe-in-pipe system to dropped anchor impacts is studied from multiple perspectives, including deformation, energy, and load transfer. The influence of pipe-in-pipe characteristic parameters, anchor characteristic parameters, centralizers, and bulkheads on the extent of impact damage is analyzed, establishing a relationship between the absorbed energy and the damage to the pipe-in-pipe. The results indicate that the impact energy primarily depends on the mass and velocity of the anchor. Energy is conserved during the impact process. It is found that even with different anchor masses and velocities, the extent of damage to the pipe-in-pipe system remains the same if the impact energy is identical. High-strength steel, large diameter, and thick-walled pipelines exhibit better resistance to impact loads. Additionally, centralizers and bulkheads mitigate the impact damage to the pipe-in-pipe system. Finally, an evaluation method for pipe-in-pipe impact damage due to dropped anchors is proposed. It is discovered that the assessment method for pipelines impacted by dropped anchors in the DNV-RP-F107 standard tends to be conservative when the impact energy is high. The findings of this study provide technical support for the integrity management of pipe-in-pipe systems.

Improving the accuracy of dynamic inclination measurement by machine learning

With the diminishing availability of oil and gas resources, the Rotary Steerable System has become increasingly important. However, the vibrations and shocks during the drilling process pose challenges to the Measurement While Drilling. In recent years, the application of machine learning in the field of petroleum exploration has gradually expanded, especially in the estimation of geological parameters and lithology discrimination. However, there is still limited research on drilling tool attitude measurement. To address the above-mentioned issues, this study proposes a method that combines drilling tool attitude sensor data with artificial neural networks to improve the accuracy of dynamic inclination measurement. This method utilizes machine learning techniques, combining real-time z-axis acceleration signals and magnetic induction signals, and employs a deep learning model to invert the x and y-axis acceleration signals, thereby achieving high-precision measurement of dynamic inclination angles. Experimental results show that Long Short-Term Memory model, under simulated measurement conditions with different rotational speeds, yields dynamic inclination curve errors ranging from 0.4° to 0.7°, significantly reducing the errors compared to the original measurements. This method not only improves the accuracy of inclination angle measurement but also demonstrates strong adaptability to different rotational speeds, providing more accurate data support for drilling operations.

A Machine Learning Approach to Adapt Local Land Use Planning to Climate Change

The impacts on living conditions and natural habitats deriving from planning decisions require complex analysis of cross-acting factors, which in turn require interdisciplinary data. At the municipal level, both data collection and the knowledge needed to interpret it are often lacking. Additionally, climate change and species extinction demand rapid and effective policies in order to preserve soil resources for future generations. Ex-ante evaluation of planning measures is insufficient owing to a lack of data and linear models capable of simulating the impacts of complex systemic relationships. Integrating machine learning (ML) into systemic planning increases awareness of impacts by providing decision-makers with predictive analysis and risk mitigation tools. ML can predict future scenarios beyond rigid linear models, identifying patterns, trends, and correlations within complex systems and depicting hidden relationships. This article focuses on a case study of single-family houses in Upper Austria, chosen for its transferability to other regions. It critically reflects on an ML approach, linking data on past and current planning regulations and decisions to the physical environment. We create an inventory of categories of areas with different features to inform nature-based solutions and backcasting planning decisions and build a training dataset for ML models. Our model predicts the effects of planning decisions on soil sealing. We discuss how ML can support local planning by providing area assessments in soil sealing within the case study. The article presents a working approach to planning and demonstrates that more data is needed to achieve well-founded planning statements.

Modeling the effect of dispersion and attenuation for frequency-dependent amplitude variation with offset

As research in oil and gas exploration progresses, unconventional resources, such as shale gas, are increasingly becoming the focal point in the global pursuit of oil and gas resource. Shale gas reservoirs significantly differ from conventional sandstone reservoirs in aspects such as rock composition, pore type, occurrence mode, fluid, etc., thereby amplifying the challenges associated with geophysical modeling and the prediction of sweet spots. Since the formation and storage of shale gas are positively correlated with shale fracturing, a modeling approach based on Chapman theory is introduced to complete frequency-dependent petrophysical modeling. Additionally, the Frequency-dependent Amplitude Variation with Offset (FAVO) technique can estimate velocity dispersion by using the reflection coefficient information related to incidence angle and frequency. This method can more effectively identify fluids within shale reservoir. However, current FAVO forward modeling only considers the velocity dispersion and attenuation at the interface, neglecting the attenuation dispersion effects during interlayer propagation. To this end, we utilize Chapman-based petrophysical modeling as a foundation and conduct seismic forward modeling studies employing the compound matrix method. Through experimental analysis, we meticulously examine the attenuation dispersion effects at interfaces and within layers. Finally, we conduct FAVO simulations that vividly delineate the interplay between reservoir parameters and seismic responses.

Analysis of the impact of geological and engineering parameters on productivity in tight oil reservoirs

AbstractTight oil resources are abundant, but the factors affecting production capacity are complex. In this paper, focusing on tight oil reservoirs, three research works were conducted. First, using the numerical simulation software, a numerical model of tight oil reservoirs was established. Second, the influence of geological parameters such as porosity and permeability on oil production were analyzed. Third, the influence of rock compression coefficient and injection fluid on tight oil production were analyzed. Results show that: (a) When the porosity is 0.05, the cumulative oil production in the first 6 years is the highest, while in the later stage of the simulation, the cumulative oil production with a porosity of 0.1 is the highest. (b) The higher the permeability, the greater the cumulative oil production. The cumulative oil production under different permeability conditions are 1392.044, 2178.805, 2939.1704, and 4038.0878 m3, respectively. (c) Under tight reservoir conditions, the impact of different rock compression coefficients on the daily oil production of oil and gas reservoirs is not very significant. (d) The recovery effect is optimal when using the N2 injection scheme. The effectiveness of the CH4 scheme is second, and there is a certain gap compared to the N2 scheme. The development plan of injecting water has the worst effect. However, compared to the depletion development model, the cumulative oil production by injecting N2, CO2, CH4, and water has all increased.

Sedimentation characteristics of surficial sediments in Baiyun Canyon area, Northern South China Sea

The Baiyun Canyon area on the Northern Slope of the South China Sea is a potential hotspot for oil and gas resource development, but the sediment characteristics and sedimentary environment in this region present challenges for offshore engineering. This study comprehensively analyzed the physical, and mechanical properties of sediments in the area using geophysical exploration, engineering geological investigation, fixed-point sampling and hydrological observation. The engineering geological characteristics and sedimentary environment of surface sediments in the Baiyun Canyon area were studied, and the relationship between physical and mechanical properties and sedimentary environment was explored. The study revealed that the sediments in this area consist mainly of organic soft clay with high water content, low density, high pore ratio, high liquid limit, high plasticity and low strength. The physical and mechanical properties of the sediments vary, with the mechanical properties exhibiting higher variability than the physical properties. The research findings offer a scientific basis for understanding the seabed soil properties for designing submarine engineering structures in the deep waters of the northern South China Sea. This study holds significant theoretical and practical implications for oil and gas exploration and offshore engineering construction.

Monsters or Victims An Ecocritical Reading of Samson and Sally and Dot and the Whale, Retellings of Moby Dick

The paper aims to explore two animations, Samson and Sally (1984) and Dot and the Whale (1986), through the lens of zoocriticism (Huggan and Tiffin) and ecocinematic analysis to show how the directors have presented the alternative version of Herman Melville’s Moby Dick in order to showcase the crises of cetaceans like whale in the present scenario of the global warming, pollution and various anthropogenic damages. Unlike many popular Hollywood movies, these two animated films do not portray whales as monsters. In many popular Hollywood ventures, we can see the representations of vengeful bloodthirsty sea creatures like sharks and whales causing shipwrecks and killing humans, just like Moby Dick did in Melville. However, Samson and Sally and Dot and the Whale propose a different version of Moby Dick, where Moby Dick is portrayed as a saviour of the whale race under the threats of whaling, oil spills, and rising temperature. Samson and Sally is a bildungsroman as it depicts the journey of a young whale in search of the mythical Moby Dick who can only save his clan from whalers who have killed his mother and other relatives. Dot and the Whale, on the other hand, points such issues like the beaching of whales and their exploitation for oil and other resources. These two animations have presented an accurate picture where animals are not presented as monsters but rather victims of human greed. Although these animations are in the anthropomorphised version, they are created to raise human awareness to protect cetaceans and marine life.

Growth, physiological and N, P, K accumulation responses of Erythropalum scandens Bl. Seedlings under different substrates

Erythropalum scandens Bl. is a medicinal woody vegetable found in southern China and parts of Southeast Asia. Studies have shown improper substrate hindered E. scandens seedling growth, causing water accumulation and nutrient deficiency. In pursuit of an ideal growth medium for E. scandens seedlings during the early stages, this study conducted a pot experiment to identify a mixed substrate with optimal water permeability and fertility. In this study, pure Alfisols soil treatment as the control (CK), and two soilless substrates (peat soil and perlite) were combined with Alfisols soil into different volume ratios, in order to better use soil resources from understory space and balance the texture of mixed substrates. The growth, physiological characteristics and nutrient status of 24-month-old E. scandens seedlings were determined after planting in different mixed ratios. The results showed that as the proportion of peat soil increased in the mix, most indexes exhibited an initial increase followed by a decline, while soluble protein content decreased consistently. Conversely, an increasing perlite ratio resulted in a general decline in most growth and physiological indexes. Root growth, biomass accumulation and chlorophyll content, peaked in the 66.67% Alfisols soil + 33.33% perlite (T4) treatment. Notably, T3 (66.67% Alfisols soil + 33.33% peat soil) showcased the best above-ground growth, while T1 (50.00% Alfisols soil + 50.00% peat soil) excelled in element content accumulation. In conclusion, the cultivation substrate should primarily consist of Alfisols soil, constituting at least 50%. The addition of peat soil enhances above-ground growth and nutrients accumulation, while perlite contributes to robust root development. One third of peat soil and a small amount of perlite can be added to the substrate during E. scandens seedling cultivation, and proper fertilization should also be used in order to increase nutrient accumulation in aboveground and underground parts. This research provides valuable insights into maximizing the potential of E. scandens seedlings through precise cultivation methods.

Development and Application of an Employee Moral Quotient (MQ) Evaluation Index System for Chinese Petroleum Enterprises

Recognizing the critical role of oil and gas resources as strategic assets and acknowledging the increasing emphasis on green development and social responsibility driven by international energy agreements and the “dual carbon” strategy, this study addresses the urgent need for a robust employee evaluation framework within China’s petroleum sector. While existing systems often prioritize competence-based indicators, they frequently overlook the crucial aspect of employee Moral Quotient (MQ). This research focuses on developing and validating a holistic, scientifically grounded, multi-dimensional, and dynamic MQ evaluation index system tailored specifically for Chinese petroleum enterprises. The study employed a mixed-methods approach, integrating a comprehensive literature review, semi-structured interviews with industry experts, and robust quantitative techniques, including the Analytic Hierarchy Process (AHP) and the entropy weight method. A two-round Delphi study, involving 18 experts from six provinces across China, ensured broad representation and facilitated the construction of the evaluation index system and the determination of indicator weights. The Delphi process achieved a high degree of expert consensus, evidenced by a 100% questionnaire response rate in both rounds, expert authority coefficients of 0.851 and 0.879, respectively, and Kendall’s coefficient of concordance of 0.243 and 0.247 (p &lt; 0.01), respectively, demonstrating strong reliability and scientific validity. The resulting MQ evaluation index system comprises eight first-level indicators and thirty-three s-level indicators, encompassing key dimensions of employee morality relevant to the petroleum industry. This comprehensive system provides a robust and objective tool for employee selection, training, performance evaluation, and career development within Chinese petroleum enterprises, supporting informed decision-making in human resource management and fostering a culture of ethical conduct and sustainable development. Furthermore, the developed framework offers valuable insights and serves as a potential model for petroleum enterprises and other resource-intensive industries globally seeking to integrate MQ assessment into their human capital management strategies.

Performance evaluation of waste phosphogypsum-based solidified sludge: From laboratory test to field application

Massive dredged sludge is being landfilled without effective use due to its high-water content and poor engineering properties, which not only leads to soil resources waste, but also occupies a large amounts of land sources. In this study, ternary stabilizer, including waste phosphogypsum (PG), ground granulated blast-furnace slag (GGBS), and lime (LM) with a mixing proportion of PG: GGBS: LM = 35:60:5, was adopted to improve the mechanical and environmental behaviors of sludge for subgrade filling purpose. The initial water content of sludge was controlled using two different dehydration methods for comparison. A series of laboratory tests, including unconfined compressive strength (UCS), organic matter content, and pH value were tested to understand its physical-mechanical properties. Thereafter, field application model equipped with a mini weather monitoring station was constructed to monitor the influence of solidified matrix on the surrounding water and soil environment. Time -dependent parameters such as plant growth, temperature, humidity, total nitrogen, phosphorus/potassium content, electrical conductivity, and pH value were monitored. Results indicate that the incorporation of PG-GGBS-LM ternary stabilizer significantly improves the mechanical and environmental properties of dredged sludge. The optimal dosage of the ternary stabilizer is 36%, which can result in a UCS value of the 2.0 MPa (slightly higher than ordinary Portland cement) after 28 days of curing. Field application reveals that plants could grow normally in solidified sludge. The environmental related parameters (i.e., total nitrogen, phosphorus/potassium content, electrical conductivity, and pH value) were similar with those in conventional planting soil, suggesting the advantage of the proposed PG-GGBS-LM ternary stabilizer in mechanical, economic and environmental aspects.