Natural Soil Research Articles

The extraction and benefits of tea tree oil

In recent times, there has been a surge in the popularity of complementary as well as alternative therapies, like tea tree (melaleuca) oil. Now available everywhere as both a pure oil and an active ingredient in numerous products, this essential oil has been utilised for almost a century in Australia. In the past, the main applications of tea tree oil have been to treat infections and inflammations. This review outlines the latest advancements in our comprehension of the antibacterial, anti-inflammatory, and therapeutic effectiveness properties of the oil and its constituents. A brief discussion of the oil's toxicity is included, along with a description of the specific mechanisms of antibacterial as well as anti-inflammatory effect. Tea tree oil balances the scalp’s natural oil production, making its useful for combating oily hair. Its antifungal properties make it effective in fighting dandruff and dry scalp conditions. This essential oil can be mixed with carrier oils or added to your regular shampoo for easy use.Bottom of Form

Dependence and sustainability: a disaggregated analysis of electricity generation in ASEAN countries

Purpose This study aims to explore the diverse sources of electricity generation (coal, natural gas, oil and hydroelectricity) and their respective associations with economic growth and environmental quality. Design/methodology/approach This study uses static panel data analysis with a random effects model for six selected ASEAN countries (Indonesia, Malaysia, Filipina, Thailand, Vietnam and Myanmar) from 1994 to 2014. Findings This study reveals that economic growth in six selected ASEAN countries is enhanced by electricity generation from all sources, while the contribution of electricity production from hydroelectricity remains the largest and strongest. There is no environmental impact of electricity production from hydroelectric, whereas fossil fuel-based electricity production emits carbon dioxide, with coal sources being the largest contributor, followed by natural gas and oil. Practical implications Based on the results, these six ASEAN countries should invest more in hydropower projects, reduce the coal mix in power generation and promote clean coal technology to improve economic efficiency and environmental sustainability. Originality/value To the best of the authors’ knowledge, no research has examined the relationship between electricity production, environmental quality and economic growth in Southeast Asian nations. Therefore, the outcome of this study is expected to provide insightful results to supplement the framing and implementation of national and collective regional strategies for sustainable electricity generation in ASEAN countries.

Biochar aided priming of carbon and nutrient availability in three soil orders of India

In recent years biochar (BC) has gained importance for its huge carbon (C) sequestration potential and positive effects on various soil functions. However, there is a paucity of information on the long-term impact of BC on the priming effect and nutrient availability in soil with different properties. This study investigates the effects of BC prepared from rice husk (RBC4, RBC6), sugarcane bagasse (SBC4, SBC6) and mustard stalk (MBC4, MBC6) at 400 and 600 °C on soil C priming and nitrogen (N), phosphorus (P), and potassium (K) availability in an Alfisol, Inceptisol, and Mollisol. BC properties were analyzed, and its decomposition in three soil orders was studied for 290 days in an incubation experiment. Post-incubation, available N, P, and K in soil were estimated. CO2 evolution from BC and soil alone was also studied to determine the direction of priming effect on native soil C. Increasing pyrolysis temperature enhanced pH and EC of most of the BC. The pyrolysis temperature did not show clear trend with respect to priming effect and nutrient availability across feedstock and soil type. MBC6 increased C mineralization in all the soil orders while RBC6 in Alfisol and SBC6 in both Inceptisol and Mollisol demonstrated high negative priming, making them potential amendments for preserving native soil C. Most of the BC showed negative priming of native SOC in long run (290 days) but all these BC enhanced the available N, P, and K in soil. SBC4 enhanced N availability in Alfisol and Inceptisol, RBC4 improved N and P availability in Mollisol and P in Alfisol and MBC6 increased K availability in all the soils. Thus, based on management goals, tailored BC or blending different BC can efficiently improve C sequestration and boost soil fertility.

Comprehensive antifungal investigation of natural plant extracts against Neosartorya spp. (Aspergillus spp.) of agriculturally significant microbiological contaminants and shaping their metabolic profile

Fungi belonging to the genus Neosartorya (teleomorph of Aspergillus spp.) are of great concern in the production and storage of berries and fruit-based products, mainly due to the production of thermoresistant ascospores that cause food spoilage and possible secretion of mycotoxins. We initially tested the antifungal effect of six natural extracts against 20 isolates of Neosartorya spp. using a traditional inhibition test on Petri dishes. Tested isolates did not respond uniformly, creating 5 groups of descending sensitivity. Ten isolates best representing of the established sensitivity clusters were chosen for further investigation using a Biolog™ MT2 microplate assay with the same 6 natural extracts. Additionally, to test for metabolic profile changes, we used a Biolog™ FF microplate assay after pre-incubation with marigold extract. All natural extracts had an inhibitory effect on Neosartorya spp. growth and impacted its metabolism. Lavender and tea tree oil extracts at a concentration of 1000 µg mL−1 presented the strongest antifungal effect during the inhibition test, however all extracts exhibited inhibitory properties at even the lowest dose (5 µg mL−1). The fungal stress response in the presence of marigold extract was characterized by a decrease of amino acids and carbohydrates consumption and an uptake of carboxylic acids on the FF microplates, where the 10 studied isolates also presented differences in their innate resilience, creating 3 distinctive sensitivity groups of high, average and low sensitivity. The results confirm that natural plant extracts and essential oils inhibit and alter the growth and metabolism of Neosartorya spp. suggesting a possible future use in sustainable agriculture as an alternative to chemical fungicides used in traditional crop protection.

Evaluation of Locally Available Calcined Clay-Based Geopolymer for the Stabilization of Expansive Soils

Geopolymers (GPs) have been effectively used as an alternative to traditional calcium-based stabilizers for treating problematic expansive soils over the last decade. However, the high cost of precursors and limited availability of traditionally manufactured GPs pose significant challenges for commercial implementation. Utilizing locally available sources to manufacture GPs could address such limitations and promote sustainable development. A research study was designed and implemented to evaluate the efficacy of locally available calcined clay-based GP stabilizers to improve the performance of expansive soils and the results were compared with lime-treated and untreated soils. An array of laboratory studies was conducted using two natural clayey soils and two types of GPs to assess improvements in several engineering properties, including unconfined compressive strength before and after capillary soaking, resilient moduli, and moisture-induced strains. Supplemental microstructural studies using X-ray diffraction, optical microscopy, and scanning electron microscope imaging were conducted to identify the mineralogical changes and detect the precipitation of new reaction products. The engineering studies demonstrated that the application of GP significantly enhanced the strength, durability, and stiffness while reducing the swelling and shrinkage strains in the GP-treated soils. Microstructural analysis revealed that the precipitated GP gels effectively coated the soil particles and provided a uniformly bonded GP–soil matrix that enhanced the engineering performance. Overall, this study provides a comprehensive understanding with respect to the potential of using locally available calcined clay-based GPs as a sustainable and durable alternative in enhancing the engineering properties of expansive soils for the long-term performance of transportation infrastructures.

Arsenic Contamination Needs Serious Attention: An Opinion and Global Scenario

Arsenic (As) contamination is a serious global concern, polluting our natural resources, including water and soil, and posing a danger to the environment and public health. Arsenic is present in the groundwater of several countries and this contaminated water is used for irrigation, drinking, and food preparation, which poses the greatest threat to public health. Nearly 106 countries are affected by groundwater arsenic contamination and an estimated 230 million individuals worldwide are exposed to its adverse health effects, including increased cancer risks, associated cardiovascular disease and diabetes, skin lesions, neurological effects, kidney damage, and foetal or cognitive-development-related complications. Arsenic is highly toxic and ranked first in the priority list of ATSDR (Agency for Toxic Substances and Disease Registry, 2022) and among the 10 chemicals of major public health concern on the World Health Organization (WHO) list. The maximum permissible level of arsenic in drinking water has been established at 10 µg/L by WHO, as well as by the Environmental Protection Agency (EPA) and European Union (EU). These regulatory standards underscore the gravity of the problem, and actions to prioritise the development of effective detection, mitigation strategies, and collaborative initiatives are necessary. This opinion article covers (i) arsenic footprints—global scenario and impact, (ii) awareness and education and (iii) mitigation approaches (detection and removal strategies) and future perspectives, which collectively will help in controlling and preventing As contamination of our global water resources. Regulatory and legislative bodies and development agencies are crucial for raising awareness and countering this alarming concern by implementing collaborative actions to protect our environment and public health and to provide safe drinking water for all.

Mechanism of improvement and best-fit models for the prediction of geotechnical properties of lime stabilized expansive soil used in pavement subgrade

The performance of a pavement mainly depends on the quality of the subgrade layer. Expansive soils (ES) are extensively found worldwide including Pakistan. The inadequate strength and swelling behaviour of these soils are the main problems in any road construction project. Several researchers in the last decades have attempted to improve expansive soil utilizing various materials such as lime, brick kiln dust and fly ash. The purpose of this research was to evaluate the effect of lime on the engineering properties of the ES of a highway subgrade in the Sialkot region of Pakistan. The influence of different lime dosages (0%, 2%, 4% and 6%) at curing ages (1, 7, 14 and 28 days) has been examined by pH tests, plasticity tests, compaction tests, unconfined compressive strength (UCS), free swell index, and California Bearing Ratios (CBR). A field CBR and plate load test (PLT) on the natural soil and optimum lime-treated soil with various curing periods have been carried out for applicability as subgrade material. The test findings demonstrated that higher lime dosages increased the strength and ultimate bearing capacity (𝑞𝑢𝑙𝑡) of improved ES and at the same time decreased the free swelling index (FSI), optimum moisture content (OMC), maximum dry density (MDD) and permanent deformation of the subgrade soil. The UCS values of soil treated with 2%, 4% and 6% lime increased almost by 324%, 523%, and 249% for unsoaked samples and 285%, 351% and 231% for soaked samples respectively as compared to the plain soil at 28 days curing period. The laboratory CBR values significantly increased 2.35-8.50 times and field CBR improved 5.6 times as compared to the plain soil. The 𝑞𝑢𝑙𝑡 of lime-treated soil increased by 162% as compared to the plain soil and permanent deformation reduced from 33 mm to 2 mm after 28 days. Furthermore, equations were developed to estimate the best fit for the prediction of various geotechnical parameters and coefficient of determination (R2 ) values for all equations were found higher than 0.90. From the results, it has been concluded that adding the optimum lime content of 4% by weight satisfies the requirement for the subgrade construction of highways and the developed expressions can provide a scientific basis for estimating the geotechnical parameters.

Environmentally Compatible Poly (Vinyl Alcohol)/Banana Peel Nano Crystals/Bentonite Clay-based Composites Films: Influence of Nano Filler on Biodegradation Behavior

Objective: The present work shows the effect of Bentonite Clay (BC) on the biodegradation behavior of Poly Vinyl Alcohol (PVA)/Banana Peel Nano Crystals (BPNC) composite films. background: Nowadays, composite films manufactured from biodegradable or partially biodegradable polymers reinforced natural fillers start to gain attention because they are considered as one of the environmentally friendly biomaterials Method: Biodegradation studies were conducted using soil burial and bacterial degradation method. The prepared composite films were characterized by scanning electron microscopy. Results: Biodegradation studies reported that the composite films were more degradable in bacterial environment as compared to natural soil burial. The addition of Bentonite Clay (BC) had negative effect on degradation rate of composite films. method: Biodegradation studies were conducted using soil burial and bacterial degradation method. The prepared composite films were characterized by scanning electron microscopy. Conclusion: PVA/BPNC/BC composite film showed less weight loss (%) as compared to PVA/BPNC composite films because BC had stabilizing effect against the microbial attack which prevents biodegradation.

Novel evaluation method based on critical arch height as instability criterion for sustaining arch locked-segment-type slopes

In sustaining arch locked-segment-type slopes, natural soil arches play a key anti-sliding role in the slope's evolution. In this study, a self-developed model test device was used to simulate the whole process of deformation evolution of sustaining arch locked-segment-type slopes, and the formation of natural sustaining arch and its locking control effect on slope stability were studied. The test results show that the continuous formation and progressive destruction of the sustaining arch were observed. The sustaining arch formed in the second time has the best locking effect, and the anti-sliding force reaches its stress peak point. However, the slope is not in a critically unstable state, instead, the stress is continuously adjusted to form a larger range of soil arch to resist the slope thrust. Consequently, the slope destabilizes until the ultimate shear strength of arch foots is exceeded, at which point the critical arch height of the arch is reached. The critical arch height mechanical model for slope stability analysis was developed based on the soil arching effect and limit equilibrium theory. The applicability of the model was demonstrated by the physical test and Xintan slope data, which can provide some guidance for early warning of landslides.

Shear behavior of thermally damaged rock using the bonded-particle model based on moment tensor

It is critical to understand the temperature-dependent shear behavior of rock in exploiting deep natural resources-geothermal energy, coal, and oil. The shear behavior of thermally damaged rock needs to be further clarified from a micromechanical perspective. In this study, a series of direct shear tests are performed on thermally damaged sandstone using the bonded-particle model (BPM) with thermal formulation to investigate the temperature-dependent behavior. The macro mechanical properties and micro acoustic emission (AE) responses based on a moment tensor algorithm are derived from numerical models to provide insight into the temperature dependence of the mechanical behavior of sandstone. The simulated results indicate that high temperature can induce microcracks, a form of thermally induced damage. Thermally induced damage is a principal cause of the degradation of rock's mechanical properties. Generally, the maximum magnitudes of tensile, shear, and implosive events that can be tolerated without damage decrease gradually as the temperature increases. Also, AE b-value are closely associated with temperature. The findings of this study provide new insights into the shear responses and failure behaviors of rocks at different temperatures, and further aid deep natural resource exploitation when thermal and mechanical properties are coupled. The findings of this study provide new insights into the shear responses and failure behaviors of rocks at different temperatures. These insights could be valuable for optimizing deep natural resource exploitation, particularly when considering the coupling of thermal and mechanical properties.

Fractal Characteristics of Natural Fiber-Reinforced Soil in Arid Climate Due to Cracking

Fractal geometry is a geometry that focuses on irregular geometric forms and can quantitatively describe rough and uneven surfaces and interfaces. As the main material for making natural fiber geotextile, rice straw fiber can reduce the direct impact of rainfall on soil and reduce the intensity of hydraulic erosion. This study investigates whether the use of rice straw fiber as an additive to reinforce arid soil can inhibit moisture evaporation and prevent cracking. Samples with different fiber contents added (0%, 1%, 2%, and 4%) are placed in an environmental chamber to simulate the effects of an arid climatic condition and control the temperature and humidity levels. The cracking process of the samples is recorded by using a digital camera, and the parameters of the evaporation and cracking processes are quantitatively examined through digital image processing. The results show that all of the samples with fiber have a higher residual water content and can retain 31.4%, 58.5%, and 101.9% more water than without the fibers, respectively. Furthermore, both the primary and secondary cracks as well as crack networks are inhibited in samples with a higher fiber content, that is, 2% or 4% fiber contents. The samples reinforced with fiber also have a smaller crack ratio. Compared with the samples without straw fiber, the final crack ratio of the samples with 1%, 2%, and 4% fiber is reduced by 8.05%, 24.09%, and 35.01% respectively. Finally, the final fractal dimensions of the cracks in samples with fiber contents are also reduced by 0.54%, 5.50%, and 6.40% for the samples with 1%, 2%, and 4% fiber, respectively. The addition of natural fiber as an additive to reduce evaporative cracking in soil can: (1) reduce the soil porosity; (2) enhance the binding force between the soil particles; and (3) block the hydrophobic channels. Therefore, the addition of rice straw fiber to soil can effectively reduce soil evaporation and inhibit soil cracking.

Phosphorus Dynamics in Stressed Soil Systems: Is There a Chemical and Biological Compensating Effect?

Here, we hypothesized the occurrence of a compensatory relationship between the application of P and different microbial communities in the soil, specifically in relation to the chemical and biological effects in the soil–plant–microorganisms’ interaction. We aimed to evaluate the plant–microbiota responses in plants grown in soils hosting distinct microbial communities and rates of P availability. Two experiments were carried out in a greenhouse. The first experiment evaluated four manipulated soil microbiome compositions, four P rates, and two plant species. Manipulated soil systems were obtained by the following: (i) autoclaving soil for 1 h at 121 °C (AS); (ii) inoculating AS with soil suspension dilution (AS + 10−3); (iii) heating natural soil at 80 °C for 1 h (NH80); or (iv) using natural soil (NS) without manipulation. The P rates added were 0, 20, 40, and 60 mg kg−1, and the two plant species tested were grass (brachiaria) and leguminous (crotalaria). Inorganic labile P (PAER), microbial P (PMIC), acid phosphatase activity (APASE), and shoot P uptake (PUPT) were assessed for each system. Brachiaria presented a compensatory effect for PUPT, whereby the addition of P under conditions of low microbial community enhanced P absorption capacity from the soil. However, in a system characterized by low P input, the increase in the soil biodiversity was insufficient to enhance brachiaria PUPT. Likewise, crotalaria showed a higher PUPT under high P application and low microbial community. The second experiment used three manipulated microbiome compositions: AS + 10−3; NH80; and NS and three P rates added: 0, 20, and 40 mg kg−1. In addition, two treatments were set: without and with mycorrhiza inoculation. Brachiaria showed an increase in the PUPT under low microbial communities (AS + 10−3; NH80) with P addition (20 and 40 mg kg−1 of P), but no mycorrhization was observed. In the undisturbed microbial community (NS), under no P input (0 mg kg−1 of P), brachiaria showed low mycorrhization and low PUPT. Finally, NS and the recommended P input (40 mg kg−1 of P) represented a balance between chemical and biological fertility, promoting the equilibrium between mycorrhization and PUPT.

The Effect of Waste Marble Dust and Corncob Ash on the Engineering and Micro-Structural Properties of Expansive Soil for Use in Road Subgrades

This research investigated the effect of Waste Marble Dust (WMD) and Corncob Ash (CCA) on expansive soil's engineering and microstructural properties. Various laboratory experiments were performed on the natural soil to ascertain its characteristics. The corncobs underwent pre-water treatment for fourteen days to remove excess potassium and increase their silica content, resulting in a rise in the silica level from 0% to 50%. At first, only WMD was added to the soil in increments of 5% to 30% using compaction and California bearing tests. The optimum dosage of 15% WMD addition yielded the best result. CCA was then incorporated by the weight of the soil from 2% to 10% in increments of 2% to the first optimum (15% WMD) to obtain the overall optimum for the study (15% WMD and 8% CCA). Stabilization of the natural soil using both materials led to the modification and solidification of the soil mass, evident by the rise in California bearing ratio values from 1.68% to 15.53% and unconfined compressive strength from 41.33 kN/m2 to 174.68 kN/m2. There was also a decrease in the soil's free swell from 120% to 15% as well as reductions in the liquid limits from 56.23% to 36.01% and in the plasticity index from 29.74% to 8.72%, respectively. The microstructural images showed the formation of cementitious compounds in the form of calcium silicate hydrate and calcium aluminate hydrate gels. The findings indicate that using WMD and CCA as a unit has great potential in enhancing engineering properties, like strength parameters and the swell potential of expansive soils.

Design of an Ultrasound Sensing System for Estimation of the Porosity of Agricultural Soils.

The design of a readily useable technology for routine paddock-scale soil porosity estimation is described. The method is non-contact (proximal) and typically from "on-the-go" sensors mounted on a small farm vehicle around 1 m above the soil surface. This ultrasonic sensing method is unique in providing estimates of porosity by a non-invasive, cost-effective, and relatively simple method. Challenges arise from the need to have a compact low-power rigid structure and to allow for pasture cover and surface roughness. The high-frequency regime for acoustic reflections from a porous material is a function of the porosity ϕ, the tortuosity α∞, and the angle of incidence θ. There is no dependence on frequency, so measurements must be conducted at two or more angles of incidence θ to obtain two or more equations in the unknown soil properties ϕ and α∞. Sensing and correcting for scattering of ultrasound from a rough soil surface requires measurements at three or more angles of incidence. A system requiring a single transmitter/receiver pair to be moved from one angle to another is not viable for rapid sampling. Therefore, the design includes at least three transmitter/reflector pairs placed at identical distances from the ground so that they would respond identically to power reflected from a perfectly reflecting surface. A single 25 kHz frequency is a compromise which allows for the frequency-dependent signal loss from a natural rough agricultural soil surface. Multiple-transmitter and multiple-microphone arrays are described which give a good signal-to-noise ratio while maintaining a compact system design. The resulting arrays have a diameter of 100 mm. Pulsed ultrasound is used so that the reflected sound can be separated from sound travelling directly through the air horizontally from transmitter to receiver. The average porosity estimated for soil samples in the laboratory and in the field is found to be within around 0.04 of the porosity measured independently. This level of variation is consistent with uncertainties in setting the angle of incidence, although assumptions made in modelling the interaction of ultrasound with the rough surface no doubt also contribute. Although the method is applicable to all soil types, the current design has only been tested on dry, vegetation-free soils for which the sampled area does not contain large animal footprints or rocks.

Global evidence of multi-dimensional asymmetric effect of energy storage innovations on environmental quality: Delineating the role of natural resources, nuclear energy and oil consumption

The strive to lower reliance on fossil fuels and transition to clean energy sources necessitates innovations in energy storage. This study empirically investigates the effectiveness of energy storage innovations towards a greener environment on a global scale. To this end, we use quarterly frequency time series data on a global scale over the period 2000 to 2020 and the estimation techniques based on the nonparametric multivariate quantile on quantile regression (MQQR), multivariate quantile regression (MQR), and Kernel-based regularized least squares (KRLS). The empirical results reveal that energy storage innovation and nuclear energy are strongly related to a decline in carbon dioxide emissions (CO2e) but natural resources and oil consumption intensify the level of CO2e across quantiles. However, the effects of energy storage innovation, nuclear energy, natural resources, and oil consumption are heterogeneous leading to an asymmetric pattern across quantile distribution. The policy implication of this study is that, on a global scale, energy storage innovation and nuclear energy provide opportunities for attaining a greener environment and more environmentally sustainable future but natural resources and oil consumption impede policies toward a sustainable environment. Therefore, our study recommends, among other things, an aggressive boost of energy storage system and nuclear energy while decreasing reliance on fossil fuels.

Reduction and transformation of Cr(VI)-associated ferrihydrite by Shewanella oneidensis MR-1: Kinetics and secondary minerals

Hexavalent chromium (Cr(VI)) could be sequestrated by soils via microbial reduction to Cr(III) and association with minerals, however, quantitative understanding of metal reducing bacteria on the coupled kinetics of Cr and Fe minerals is still lacking. Here, microbial-mediated ferrihydrite transformation and reductive sequestration of Cr(VI) were investigated with Shewanella oneidensis MR-1 under varying Cr/Fe ratios. Quantitative results depicted that the contents of magnetite from ferrihydrite transformation decreased from 70 % to 22 % after 288 h as Cr/Fe ratios increased from 0 to 8 × 10−3, and reductive transformation rates increased with decreasing Cr/Fe ratio. Elemental mapping and line scan analyses at nano-scale revealed that Cr(VI) was evenly combined within fresh ferrihydrite, and a part of produced Cr(III) was doped into the crystal lattice of magnetite and goethite. Cr may be sequestrated by secondary Fe minerals via structural substitution, surface complexation, and physical encapsulation. Microscopy-based results exhibited that more Fe minerals adsorbed on the surface of cell and less cells were lysed at low Cr/Fe ratios. Confocal laser scanning microscopy depicted that less cells were alive at high Cr/Fe ratios. The amplification of extracellular electron transfer-associated genes was downregulated as Cr/Fe ratios increased. The Cr/Fe ratios could affect cell activity, the combination with Fe minerals, and Mtr gene expression, thus controlling the reductive sequestration of Cr(VI) and phase transformation of ferrihydrite. A kinetic model has been established by combining elementary reductions, and it could well describe Cr(VI) reduction and Cr(III) incorporation under various Cr/Fe ratios during dissimilatory Fe reduction process. These findings could broaden our knowledge of quantifying the migration and transport of Cr in anoxic Cr-contaminated soil environments, and could be useful for simulating Cr dynamic behaviors in the natural soil, aquatic, and sediment environments.

Novel enhancement of interfacial interaction and properties in biodegradable polymer composites using green chemically treated spent coffee ground microfiller

This study investigates the potential of utilizing green chemically treated spent coffee grounds (SCGs) as micro biofiller reinforcement in Poly-3-hydroxybutyrate-co-3-hydroxyvalerate (PHBV) biopolymer composites. The aim is to assess the impact of varying SCG concentrations (1 %, 3 %, 5 %, and 7 %) on the functional, thermal, mechanical properties and biodegradability of the resulting composites with a PHBV matrix. The samples were produced through melt compounding using a twin-screw extruder and compression molding. The findings indicate successful dispersion and distribution of SCGs microfiller into PHBV. Chemical treatment of SCG microfiller enhanced the interfacial bonding between the SCG and PHBV, evidenced by higher water contact angles of the biopolymer composites. Field Emission Scanning Electron Microscopy (FE-SEM) confirmed the successful interaction of treated SCG microfiller, contributing to enhanced mechanical characteristics. A two-way ANOVA was conducted for statistical analysis. Mass losses observed after burying the materials in natural soil indicated that the composites degraded faster than the pure PHBV polymer suggesting that both composites are biodegradable, particularly at high levels of spent coffee grounds (SCG). Despite the possibility of agglomeration at higher concentrations, SCG incorporation resulted in improved functional properties, positioning the green biopolymer composite as a promising material for sustainable packaging and diverse applications.

Geofoam Block in Soft Soil Embankment Applications: A Review

The major issues of building a road over soft soils are low bearing capacity and large settlements. The challenges of road construction on soft soils are enormous, so innovative and environmentally friendly methods are required. Geofoam is a type of lightweight infill material and was already used in Norway in road construction applications in 1972. Using Geofoam reduces compacted fill by 40%, less excavation required and less pulverization of native soil making this a time-saving and economically and environmentally viable solution. The purpose of Geofoam backfill is for lightweight backfilling, reducing soil pressure. Geofoam blocks can be used as a substitute for soft soil fill or as fill on top of soft soil as subgrade for pavement. This paper discusses the latest developments on the various applications of Geofoam blocks as backfill in soft soils presented based on information provided by the author.

The Fungal Functional Guilds at the Early-Stage Restoration of Subalpine Forest Soils Disrupted by Highway Construction in Southwest China

Soil fungi often operate through diverse functional guilds, and play critical roles in driving soil nutrient cycling, organic matter decomposition and the health of above-ground vegetation. However, fungal functional guilds at the early-stage restoration of disrupted subalpine forest soils remain elusive. In the present study, we collected 36 soil samples along an altitudinal gradient (2900 m a.s.l., 3102 m a.s.l., and 3194 m a.s.l.) from cut slopes (CS) (from Wenma highway) and natural soils (NS) at the Miyaluo of Lixian County, Southwest China. By applying nuclear ribosomal internal transcribed spacer (ITS) sequencing, this study revealed the ecological characteristics of fungal functional guild in the early-stage restoration of cut slope soils. The results showed that the predicted prevalence of ectomycorrhizal fungi decreased, while plant pathogens and arbuscular mycorrhizal fungi increased in CS. In the high-altitude regions (3102 m a.s.l. and 3194 m a.s.l.), the differences in communities between natural and cut slope soils were more pronounced for total soil fungi, soil saprotroph, litter saprotroph, arbuscular mycorrhizal fungi and ectomycorrhizal fungi, in contrast to the low altitude communities (2900 m a.s.l.). An opposite pattern was evident for plant pathogens. Variations in the differences of both soil properties (mainly soil pH) and community assembling processes (e.g., heterogeneous selection, dispersal limitation and drift) between natural and cut slope soils across the altitudinal gradient likely shaped the shifting patterns of community difference. This study provides valuable insights for devising restoration approaches for cut slopes in subalpine forest ecosystems, emphasizing the importance of taking soil fungal functional guilds into account in evaluating the restoration of cut slopes, and underscoring the necessity for increased attention to the restoration of soil fungi in cut slopes at the high-altitude ecosystems.

The Nutritional Content of Traditional Corn Bread and its Carotenoid Values

Commonly found in nature are the pigments in many food groups. It has a significant function in the human body, such as strengthening immune system and specifically due to its provitamin A and antioxidant effects. With carotenoids’ chemical functions, they help to prevent a number of health problems before they occur in the body and to improve diseases existing. The aim of the study is to determine the carotenoid and nutritional elements of corn bread that was produced with flour obtained from local corn in Turkey. Experimental research method was used in the research and these samples were subjected to chemical analysis. Within the scope of the study, lutein, beta carotene, lycopene, energy, moisture, ash, protein, carbohydrate, dietary fibre, and fat analyses were made for three samples: corn flour, bread dough mix and baked corn bread. As a result of the analysis, it was determined that the prepared corn bread is rich in lutein, protein, dietary fibre and natural oil and it is valuable in terms of the energy that it provides, but after the heat treatment, some of the nutrients are decreased.