Minerals Potassium Research Articles

Application of waste eggshells elevates phytoremediation efficiency of Pb-Zn mine-contaminated farmland and mitigates soil greenhouse gas emissions: A field study

Remediating heavy metal (HM)-contaminated farmlands and sequestering soil carbon for emission reduction have been prominent topics in environmental research in recent years. However, few studies have looked into the soil greenhouse gas (GHG) impacts of growing hyperaccumulators in composite HM-contaminated farmland, as well as agronomic measures to remediate soil HMs while mitigating GHG emissions. To investigate fertilization measures to improve phytoremediation efficiency and mitigate GHG emissions, S. photeinocarpum was planted with three different fertilization measures on farmland contaminated by lead-zinc (Pb-Zn) mines (1200 kg ha−1 eggshell, 125 kg ha−1 28-homobrassinolide, and 16.7 kg ha−1 mineral potassium fulvic acid) during its growth period. The findings are as follows: Eggshell application significantly enhanced the translocation factor (TF) of Pb, Zn, and cadmium (Cd) from the roots to the shoots of Solanum photeinocarpum. Moreover, eggshells notably increased the bioaccumulation factor (BCF) of Cd and Pb in plant shoots by 120.75% and 159.09%, respectively. Regarding GHG emissions, the combined application of eggshells and 28-homobrassinolide substantially lowered the global warming potential (GWP) of the soil. Correlation analyses revealed that eggshell application increased the relative abundance of the Gemmatimonadota bacterial phylum in the soil, facilitating Pb and Cd migration from the roots to shoot tissues in S. photeinocarpum. Eggshell use inhibited nitrate nitrogen (NO3−-N) transformation into nitrous oxide (N2O) by the Myxococcota bacterial phylum and reduced N2O release from the soil. The application of low-cost eggshells can achieve a win-win situation of soil HM remediation and GHG emission reduction, as well as provide simple and scalable management measures for HM-contaminated farmland.

Microbiomes-Plant Interactions and K-Humate Application for Salinity Stress Mitigation and Yield Enhancement in Wheat and Faba Bean in Egypt’s Northeastern Delta

Salinity, resulting from climate change and excessive mineral fertilization, burdens farmers and negatively impacts soil and water ecosystems in the Northeastern Nile Delta. Organic and biological approaches are crucial for addressing these issues. This study examined the effects of individual and combined inoculations with cyanobacteria, yeast, and Arbuscular Mycorrhizal Fungi (AMF), with or without K-Humate and reducing Nitrogen, phosphorus and potassium (NPK) mineral fertilizers application rates to crop quality of wheat and faba bean. In preliminary laboratory experiments, the interactive effects of these microbiomes on plant antioxidant and soil enzyme production were examined under salinity stress. Results showed that co-inoculation, especially with K-Humate, yielded superior outcomes compared to individual inoculations. These findings were validated by a field trial conducted in saline-alkaline soil in the Northeastern Nile Delta region. All biological treatments 25% of recommended doses, and enhancing salinity tolerance, increasing yield, and improving enhanced rhizosphere microbial activity, including soil enzyme activity, AMF colonization, spore density, and the total numbers of bacteria, cyanobacteria, and yeast. These effects were further amplified by K-Humate and were more pronounced with combined inoculations than with individual ones, leading to improved soil fertility and significant increases in both crop quantity and quality compared to control treatments. The triple treatment, combining cyanobacteria, yeast, and mycorrhizae in the presence of K-Humate while reducing the mineral NPK rate by 75%, achieved superior increases in the productivity of wheat grains and faba bean seeds, reaching 54.72% and 128.92%, respectively, compared to the 100% NPK mineral control. This treatment also significantly improved crop quality, with notable increases in nitrogen, potassium, phosphorus, and protein percentages in wheat grains and faba bean seeds. Microbiomes-interaction increased potassium uptake over sodium, enhancing the plant’s potassium/sodium ratio and improving salt stress tolerance. This approach reduces reliance on costly mineral fertilizers, enabling bio-organic farming in marginal lands, optimizing resource utilization, and preserving natural resources.

Typochemistry and possible sources of ferrosaponite with Ce–Cu–Ni from the metabasalts of the Northern Ural

We studied metabasites from metamorphic complexes located in the northern part of the Lyapin anticlinorium of the Subpolar Urals and the Kharbey anticlinorium in the Polar Urals of the Central Ural Uplift, which are part of the Arctic zone. For the first time, ferrosaponite containing copper, nickel, and rare earth metals has been identified in these metabasites. The morphological and typochemical characteristics of ferrosaponite were examined using electron microscopy. In the Polar Urals, ferrosaponite is found in the almandine eclogite of the Marunkeu eclogite-amphibolite gneiss. The mineral is associated with garnet, quartz, pyroxene, muscovite, amphibole, and sulfides. The general formula for the mineral from almandine eclogite: (Ca0,06–0,27K0,01–0,06Се0,01)∑0,13–0,31(Fe2+ 1,67–2,21Mg0,51–0,84 Cu0,01–0,09Ni0,03–0,11)∑2,25–3,08[(Si2,84–3,08Al0,92–1,16)∑4,00O10](OH)2 ×3,55–3,83H2O. In the Subpolar Urals, this mineral was examined in a sample of garnet-amphibole-biotite-plagioclase-quartz shale, where it occurs in association with other minerals: amphibole, plagioclase, quartz, epidote, biotite, zircon, albite, titanite, apatite, and sulfides. The general formula of the mineral: (Ca0,14–0,22K0,01–0,02Се0,01)∑0,15–0,23(Fe2+ 1,24–2,22Mg0,76–0,97)∑2,17–3,15 [(Si2,86–2,96Al1,04–1,14)∑4,00O10](OH)2 ×3,41–4,47H2O. It is assumed that ferrosaponite forms through a hydrothermal-metamorphic process during the late fluid stage of rock transformation. Feldspars and biotite serve as sources of potassium and aluminum, while hornblende, pyroxenes, and epidote are the primary suppliers of magnesium and iron. In the chemical composition, alongside the main components of the mineral—potassium, calcium, magnesium, aluminum, silicon, and iron—copper, nickel, and rare earth metals were also detected. Under the influence of fluids, copper and nickel may have been derived from replaced sulfides, while cerium could have been introduced from allanite, apatite, and other minerals containing rare earth elements. Continued study of the mineragenic features of metamorphic rocks in the Arctic regions of the Urals is essential for a comprehensive assessment of their resource potential, as well as promising sources and concentrators of rare metals.

The Effect of Mocaf Flour and Yellow Pumpkin Flour (Cucurbita Moschata) Proportion on the Acceptability and Physicochemical Quality of Wet MI

Overcoming dependence on wheat flour as raw material, researchers want to develop a wet noodle product by using mocaf flour to substitute wheat flour and adding pumpkin flour to increase the nutritional value of wet noodles, namely potassium minerals as an alternative main food that can help lower blood pressure in hypertension sufferers.To determine the effect of the proportion of mocaf flour and pumpkin flour on the physicochemical quality of wet noodles. This type of research uses an experimental study design with a Completely Randomized Design (CRD). The comparison of the proportions of mocaf flour and pumpkin flour is P0 (100g : 0g), P1 (95g : 5g), P2 (90g :10g), P3 (85 g :15g), P4 (80g :20g). Physical quality and chemical quality test data were analyzed using the Independent T-test. The research results show that the percent water absorption capacity; percent elongation; potassium levels; and sodium levels, namely P0 (58.5% ; 19.8% ; 16.5mg/100 g; 5.64 mg/100g), P2 (70.3% ; 8.8% ; 55.95 mg/100g ; 5.55 mg/100g). The best treatment P2 does not meet the adult RDA percentage and cannot be classified as high in potassium. Wet noodle products cannot yet be used as an alternative to foods high in potassium for preventing hypertension.

EXAMINATION OF THE COMPOSITION OF WHEY FROM MIXED CHEESE

In recent years, the ingredients of milk represent a functional food, because their use has a great effect on health. Whey is a byproduct of cheese production, which was previously considered waste. Whey proteins strengthen the immune system by helping the body produce the antioxidant glutathione, which protects against free radicals, pollution, toxins and infections. In this research we examine the composition of whey (minerals: Ca, K, Fe and P, total proteins and albumins) from mixed cheese from the "Ideal Shipka" dairy factory - Bitola. All parameters were determined spectrophotometrically, spectrophotometric, photometric - colorimetric and nephelometric methods were applied to prove the amount of certain components present in the whey composition. From the obtained results we can see that whey has the highest amount of total proteins, it contains 17.6 g/L, from which amount of albumen is 1,99 g/L. Of the minerals, the highest value was obtained for potassium 26,6 mmol/l, followed by calcium 9,47 mmol/l, amount of phosphorus was 9,39 mmol/l, while iron is found in a very small percentage 11,74 µmol/l. From the research we can conclude that whey contains a large percentage of total proteins, and of the minerals potassium. Thus, whey can be used as a dietary supplement for protein and potassium and it is attractive product for both the food and pharmaceutical industries and consumers.

Composition and Pharmacological Benefits of Banana Blossom: A Brief Review

One of the earliest crops cultivated in emerging nations like India is the banana. Their nutritional and pharmacological profiles are good. Every part of the banana plant has a different medical purpose. The banana plant is regarded as a gift from nature to humanity because of its many nutritional, medicinal, pharmacological and physiological advantages. It is the antioxidant powerhouse that includes phytonutrients, phenolics and polyphenols. The minerals potassium, iron, zinc, phosphorus and the vitamins C, B2, B6, B5, E and A are abundant in banana flowers. Bananas and its components also include significant concentrations of phytochemicals such as quercetin, lectin, alkaloids, dopamine, flavonoids and tannins. Because of its many uses and potential, bananas and their by-products- leaves, fibers, peels and fruits are used in both the food and non-food industries to make a variety of goods, including ice cream, chocolates, pickles, jam, jellies, candies, pasta, breads, ropes, clothes and mats. In most parts of the world, it is still one of the underappreciated meals while having such effective qualities. Thus, the focus of this paper is on the value of bananas and the ability of banana blossoms to improve people¢s health in a variety of ways. It also emphasizes the necessity to raise public knowledge of bananas because they are beneficial in a number of ways.

Quantitative records of paleotemperature in Qarhan Salt Lake, Qaidam Basin and its relationship with potassium deposits

Qarhan Salt Lake, located in the Qaidam Basin on the Qinghai-Tibet Plateau in northwestern China, is the largest potash production base in China. The main potash deposit in Qarhan Salt Lake is a comprehensive deposit in which the liquid potassium resources dominated by potassium-rich and lithium-rich brine coexist with the low-grade solid potassium salt deposit composed of solid potash minerals (polyhalite, carnallite, sylvite). Polyhalite is one of the representative potassium minerals, widely distributed in the Bieletan area of Qarhan Salt Lake, coexisting with halite, and its deposition indicates that the paleo-temperature of brine in this area once fluctuated obviously. Twenty core samples from two boreholes in the Bieletan area of the Qarhan Salt Lake were subjected to fluid inclusions thermometry, and homogenization temperatures reflecting the brine temperatures during the precipitation of evaporite minerals in the Salt Lake were obtained, ranging from 12.4 to 28.9 °C and 9.2 to 19.8 °C, respectively. By scanning electron microscopy, acicular polyhalite and pompom-like aggregate of polyhalite have been identified in the sampling layer, indicating that evaporite deposition have reached the stage of potassium salt deposition. The temperature fluctuations of the fluid inclusions and the elemental chemical data are compared vertically, and the sections with significant temperature fluctuations are close to the layers where polyhalite were deposited. It shows that the paleo-temperature fluctuation impact the sedimentary environment of brine, and then affected the polyhalite deposition of Qarhan Salt Lake.

Dietary Minerals and Incident Cardiovascular Outcomes among Never-Smokers in a Danish Case-Cohort Study.

Background: Diet is known to impact cardiovascular disease (CVD) risk, but evidence for the essential minerals of magnesium (Mg), calcium (Ca), and potassium (K) is inconsistent. Methods: We conducted a case-cohort study within a non-smoking subgroup of the Danish Diet, Cancer and Health cohort, a prospective study of 50-64-year-olds recruited between 1993-1997. We identified incident heart failure (HF), acute myocardial infarction (AMI) and stroke cases through 2015 with an 1135-member subcohort. We measured the dietary intake of minerals, also known as elements, and calculated a combined dietary intake (CDI) score based on joint Ca, Mg and K intakes (mg/d) from Food Frequency Questionnaires. We estimated adjusted hazard ratios (HRs) with Cox proportional hazard models. Results: Most HRs examining associations between CDI score and CVD were null. However, the third quartile of CDI was associated with a lower risk for heart failure (HR: 0.89; 95% CI: 0.67, 1.17), AMI (HR: 0.79; 95% CI: 0.60, 1.04), and stroke (HR: 0.63; 95% CI: 0.44, 0.88). Conclusions: We did not find consistent evidence to suggest that higher levels of essential minerals are associated with incident HF, AMI, and stroke, though results suggest a potential U-shaped relationship between select minerals and CVD outcomes.

Warming enhanced the interaction effects of fungi and fungivores and soil potassium mineralization in tropical forest

Potassium (K) cycling in forest systems has received less attention than nitrogen (N) and phosphorus (P) cycles, despite its critical role in maintaining primary production and regulating water economy and use under climate warming. This study conducted a 10-year study in which we translocated dominant tropical forest tree seedlings and underlying soil (i.e., in situ soil) from high-altitude sites (600 m a.s.l.) to lower altitude sites at 300 m a.s.l. (+1.0 °C) and 30 m a.s.l. (+2.1 °C) to simulate climate warming in southern China. We investigated soil microbial and nematode communities, soil and foliar K concentrations at the aggregate level, and tree growth under different altitude sites. Microbial community was characterized by high-throughput sequencing, nematodes were identified to the genus level using microscope. The findings revealed that warming treatments significantly (p < 0.01) increased soil fungal gene abundance (+78 % at 300 m and +62 % at 30 m), fungal/bacterial abundance ratio (+121 % at 300 m and +101 % at 30 m), and soil fungivore abundance (+274 % at 300 m and +233 % at 30 m). These results indicate a shift in the soil decomposition pathway from bacterial to fungal-based channels. In addition, warming amplifies the interactions between fungi and fungivores. Aggregates had few effects on microbial biomass, but had significant effect on nematode abundance. Soil microcosm experiments consistently demonstrated that addition of the dominant fungivore Aphelenchoides significantly (p < 0.05) enhanced soil-exchangeable K by stimulating fungal gene abundance and activity. Furthermore, warming-induced changes in forest communities were observed. At the species-specific tree level, Syzygium rehderianum demonstrated the ability to take advantage of this scenario, exhibiting increased K uptake (−4% at 300 m and +32 % at 30 m). This may be attributed to the species being ectomycorrhizal-forming, where colonizing root surfaces can mobilize interlayer and structural K from the minerals. In contrast, Machilus breviflora exhibited lower foliar K concentrations (−42 % at 300 m and −41 % at 30 m) and reduced growth. However, warming had little effect on Schima superba, Myrsine seguinii, Itea chinensis, and Ardisia lindleyana growth. Warming-induced changes in the plant–soil system K cycle highlight the emergence of a new ecosystem structure with different soil web structures and distinct plant community species composition. Our results prompt further research to understand the microbiome-mediated complexities of understudied nutrient cycles, which are likely to be further altered in the future owing to climate change.

Contribution of Using Filter Cake and Vinasse as a Source of Nutrients for Sustainable Agriculture—A Review

The use of filter cake and vinasse in agriculture began in the 1970s and intensified in the 1990s. Currently, the Ukraine war and the high value of fertilizers have created opportunities for fertilization programs in agricultural systems with sustainable goals. This review presents updated data (1988–2024) and a discussion on the potential agricultural use of filter cake and vinasse and indicates the current progress of research on this subject in addition to future prospects. Filter cake stands out due to the formulation of organomineral fertilizers with direct application of composted or fresh forms, favoring the agronomic efficiency of phosphorus. The use of vinasse in fertigation is feasible and replaces potassium mineral fertilizers and other nutrients following an organic matrix. Future perspectives point to the agricultural use of filter cake and vinasse on a sustainable basis from different approaches. The aim is to potentiate their benefits in the soil-plant-atmosphere system. It is noteworthy that filter cake or vinasse, when combined with growth-promoting bacteria in irrigated crops, can nullify the negative effects of climate change due to increased productivity and, at the same time, meet the United Nations Sustainable Development Goals by 2030. This contributes to facing global challenges related to food security by recycling nutrients for agriculture and generating clean bioenergy from sugarcane biomass.

EFFECT OF FOLIAR FEEDING OF POTASSIUM FERTILIZER ON THE NUMBER OF STEM AND STORAGE RATE OF HEMP VARIETY “UZBEK-2268”

In this article, the effect of foliar feeding of potassium fertilizer on the background of mineral fertilizers on the number of stems and the level of preservation of hemp variety “Uzbek-2268” has been proven. Against the background of mineral fertilizers in the experiment, potassium mineral fertilizer was applied to the level of preservation of the number of stems at the end of the vegetation period in the variant given at 48 kg/ha in the phases of 2-3 true leaves of the hemp plant, budding-flowering and flowering-fruiting, it was found that it was 171.2 thousand bushes/ha, showing a high result compared to the options.

Paddy management controls potassium release from minerals in purple soils after 40 years of cultivation

AbstractThis study explored the mechanisms underlying the release and transformation of potassium from potassium‐rich minerals in paddy soils derived from purple soils. While potassium is abundant in these minerals, it is typically insoluble and inaccessible to plants. The agricultural practices employed in paddy soils may activate insoluble mineral potassium, potentially reducing potassium fertilizer applications. The activation of mineral potassium not only helps alleviate the dependence on soluble potassium fertilizers in rice cultivation, but also contributes to enhancing food security and sustainable agricultural development. Despite these potential benefits, the transformation pathways of mineral potassium in paddy soils remain unclear, posing an important science question that requires further investigation. This study collected data from a long‐term fertilizer experiment of paddy soils derived from purple soils with abundant potassium‐rich minerals (1982–2019, rice‐wheat rotation). The results revealed that paddy management could drive the transformation of potassium in illite minerals in paddy soils and meet the long‐term growth needs of crops. Submergence reduction significantly increased the concentration of positive ions such as Fe2+ and Ca2+ and provided a pathway for the free movement of ions, promoting the substitution of these ions with interlayer potassium of minerals. This substitution and alternating reduction and oxidation conditions played an important role in the transformation of potassium in illite minerals. The study indicates the promising potential for using crushed illite rocks in rice paddies as a substitute for traditional potassium fertilizers.

Chemical, microbial, and volatile compounds of water kefir beverages made from chickpea, almond, and rice extracts

This study aims to assess the microbial, nutritional, volatile, and sensory characteristics of rice, almond, and chickpea water kefir beverages during refrigerated storage. Plant-based kefirs contained significant amounts of lactic acid bacteria and yeasts. The microbial content of kefirs was stable during 14-day refrigerated storage. Lactic acid, acetic acid, and tartaric acid are commonly detected organic acids in kefir samples. Almond and chickpea kefirs were rich in potassium mineral. Almond kefir had the highest ethanol content among plant-based kefirs, followed by chickpea and rice-based kefirs. Ethyl acetate, acetic acid, propionic acid, hexanoic acid, and benzenemethanol were identified as key volatile compounds in almond kefir and chickpea kefir samples using a GC–MS detector during water kefir fermentation. According to sensory analysis results, significant differences are present for all test parameters except odor. Almond kefir was the most accepted, while the other two kefir samples were below the general acceptance level (P < 0.05).

Pedogenesis of pelitic rocks of the Serra da Saudade Formation - Bambuí Group

ABSTRACT Serra da Saudade Formation corresponds to the upper part of the stratigraphic column of the Bambuí Group. Few studies have addressed the soil properties and pedogenesis of the pelitic rocks rich in potassium minerals of this formation. This study analyzed siltstone-derived soils, some of which are glauconitic (green siltstone; “verdete”), to understand the role of the main pedogenetic factors and processes in the landscape of the Central-West region of the Minas Gerais State, covered by Cerrado vegetation. Nine soil profiles were described, and their morphological, physical, chemical and mineralogical properties were analyzed. Soils were classified as Neossolos Litólicos (P1, P3, P6, P8 and P9), Cambissolos Háplicos (P2 and P5), Argissolo Vermelho-Amarelo (P4) and Argissolo Acinzentado (P7). The main active pedogenetic processes identified in the study area are melanization, goethization, argiluviation and elutriation. These are essentially controlled by the nature of the parent material and position of the soil in the relief. Soils are typically shallow, dystrophic, highly Al-saturated and contain essentially quartz and micas in the coarse fractions (sand and silt) and illite/glauconite and kaolinite in the clay fraction. In soil environments with siltstone and green siltstone under “dry forests”, the soil water pH was higher and high levels of exchangeable calcium and magnesium, a eutrophic character and high-activity clay were observed. Barium, chromium, lead and zinc contents were high in all studied soils. Green siltstone-derived soils have peculiar physical and chemical properties, divergent from those developed from other glauconitic rocks on the Earth surface. However, greenish tones in horizons are common in all these soils.

Efficiency of Desiccation, Decomposition and Release of Nutrients in the Biomass of Forage Plants of the Genus Brachiaria After Intercropping with Sorghum in Integrated Systems for Soybean Productivity

ABSTRACT The implementation of more sustainable soil management strategies, such as the use of cover crop for no-till system with crop rotation, can help increase nutrient use efficiency and consequently decrease the use of mineral fertilizers for agriculture. In this context, the objective was to evaluate the efficiency of desiccation, decomposition and release of nutrients in the biomass of forage plants of the genus Brachiaria after intercropping with sorghum in integrated systems for soybean productivity. The experiment was conducted in the field in two agricultural seasons in randomized block design with four repetitions. The treatments consisted of biomass obtained after sorghum intercropping with forage plants of the Brachiaria genus (Brachiaria ruziziensis, Brachiaria brizantha cv. Marandu, Brachiaria brizantha cv. Xaraés, Brachiaria brizantha cv. BRS Piatã, Brachiaria brizantha cv. BRS Paiaguás, Brachiaria cv. BRS Ipyporã), sorghum biomass in monoculture, which after cutting for grain production, remained fallow for one year and an additional soybean treatment without soil cover biomass. The results showed that Cropping systems on sorghum and forage biomass resulted in a 25.64% increase in soybean yields compared to soybeans grown without soil cover. The use of tropical forage as a cover crop in integrated systems proved to be an efficient technique for biomass production, in order to minimize the effect of water deficit during soybean development, and nutrient cycling, which resulted in the replacement of mineral potassium fertilization for the no-till soybean system, by making better use of soil nutrients and contributing to greater sustainability.

Studying the Efficacy of Some Organic Compounds as a Source of Potassium Fertilization and their Effect on the Wheat-Peanut Crop System in Sandy Soil

To encourage sustainable agriculture and increase net revenue for the agricultural community, the use of expensive chemical fertilizers should be reduced and replaced with locally produced organic byproducts. For this reason, a field experiment was conducted on sand soil at Ismailia Agric. Res. Station in Ismailia Governorate, Egypt, to evaluate the impact of various organic K rates 0, 50%, 75%, and 100% from the recommended plant dose) and three different K organic sources i.e., seaweed (SWE), yeast sludge (YS), and filter mud cake (FMC), in two successive seasons of wheat (Triticum sativac. v. Giza 168) as a winter crop and peanut (Arachis hypogaeac. v. Giza 6) as a summer crop season; to study how responsive they are to different potassium rates and sources applied to crop productivity. After both crops were harvested, the chemical features of the soil were also assessed. The current findings state that the use of varied organic K rates and sources boosted the yield components of wheat and peanut crops, as well as the nutritional total content in straw, grains, or seed of both wheat and peanut, as compared to the control treatment. Furthermore, the application of all treatments improved pH, EC, OM, and cation exchangeable capacity (CEC); the availability of P, K, and soluble K followed a similar pattern after the wheat-peanut crop was harvested. Furthermore, the highest increases resulted from 75% of the recommended K dose, and the best organic sources of K were YS and SWE for wheat and peanut, respectively. In conclusion, the use of tested organic potassium sources is a good alternative to mineral potassium fertilizers, is economical, which is reflected in crop yield, and is environmentally friendly.

Melting Processes of Pelitic Rocks in Combustion Metamorphic Complexes of Mongolia: Mineral Chemistry, Raman Spectroscopy, Formation Conditions of Mullite, Silicate Spinel, Silica Polymorphs, and Cordierite-Group Minerals

Melted rocks (clinkers and paralavas) of the Mongolian combustion metamorphic (CM) complexes were formed during modern and ancient (since the Quaternary) wild-fires of brown coal layers in the sedimentary strata of the Early Cretaceous Dzunbain Formation. According to XRD, Raman spectroscopy, and SEM-EDS data, cordierite, sekaninaite, indialite, ferroindialite, silica polymorphs, mullite, Fe-mullite, anhydrous Al-Fe-Mg silicate spinel (presumably new mineral), and other phases were identified. It has been established that isomorphic impurity of potassium in the cordierite-group minerals does not correlate with their crystal structure (hexagonal or orthorhombic). Indialite and ferroindialite retained their hexagonal structure in some fragments of the CM rocks, possibly due to the very fast cooling of local zones of sedimentary strata and the quenching of high-temperature K-rich peraluminous melt. Clinkers, tridymite–sekaninaite, and cristobalite–fayalite ferroan paralavas were produced by partial melting of Fe-enriched pelitic rocks (mudstone, siltstone, and silty sandstone) in a wide temperature range. The formation of mullite, Fe-mullite, and Al-Fe-Mg silicate spinel in clinkers developed from dehydration–dehydroxylation and incongruent partial melting of Fe-enriched pelitic matter (Al-Mg-Fe-rich phyllosilicates, ‘meta-kaolinite’, and ‘meta-illite’). Large-scale crystallization of these minerals in the K-rich peraluminous melts occurred, presumably, in the range of T &gt; 850–900 °C. The subsurface combustion of coal layers heated the overburden pelitic rocks from sedimentary strata to T &gt; 1050 °C (judging by the formation of cordierite-group minerals) or locally till the melting point of detrital quartz grains at T &gt; 1300 °C and, possibly, till the stability field of stable β-cristobalite at T &gt; 1470 °C. Ferroan paralavas were formed during the rapid crystallization of Fe-rich silicate melts under various redox conditions. From the analysis of the liquidus surface in the Al2O3–FeO–Fe2O3–SiO2 major-oxide system, it follows that the least high-temperature (&lt;1250 °C) and the most oxidizing conditions occurred during the crystallization of mineral assemblages in the most-enriched iron silicate melts parental for cristobalite–fayalite paralava.

Evaluation of the Shale Impact on Reservoir Characterization, the Jeribe Carbonate Reservoir in an Oilfield Northern Iraq as a Case Study

The shale content and mode of distribution, along with their impact on the reservoir properties of the Jeribe Formation, were investigated using the available log data in the two selected wells, NET-10 and NET-12, of an oilfield northern Iraq. The dolomite and dolomitic limestone lithology of the formation contains different ratios of shale, with the highest near the middle part of the formation. Horizons of 70 to 99% shale content were identified, but the general ratios are ranging between 10% and 50%. The data from the Spectral Gamma ray log revealed that the shale content of the formation is mostly composed of low Potassium minerals such as Chlorite and Montimorlinite, with appreciable percentages of Illite. The low Th/U ratios along the formation indicated a reduced condition of deposition except for about 2-3 meters of the upper part of the formation in the well NET-10, which looks to be precipitated in a natural depositional environment. Dispersed, Laminar, and Structural modes of shale distribution co-exist within the formation in both studied wells. As the different modes of shale distribution have different impacts on the porosity and permeability of the reservoir rocks, the decrease and increase in the shale content did not perfectly correspond with an opposite fluctuation in the porosity values of the formation. The shale content in the formation has an impact on the porosity calculation by overestimating it by about 4–5% and subsequently underestimating the water saturation by 9% in the well NET-10 and 7% in the well NET-12.

Impact of Potassium Inoculants and Biotite on Soil Microbial Population and Enzymatic Activity under Maize (Zea mays L.) Cultivation in Gangetic Plains

The study explores the impact of potassium inoculants and black mica on soil microbial populations and enzymatic activity in maize cultivated soils. Microbial communities fueled by root exudates play essential roles in nutrient cycling, plant health, and soil structure. This study investigates the effects of potassium-solubilizing bacteria (KSB) and mineral potassium on microbial populations and enzymatic activity across different growth stages of maize. The experiment was conducted in randomized block design with 14 treatments, including combinations of KSB isolates, mineral potassium, and inorganic potassium. Microbial populations (bacteria, fungi, actinomycetes, and KSB) were quantified using serial dilution and plating techniques. Enzymatic activities (dehydrogenase, phosphatase, and urease) were assessed to understand nutrient interactions and microbial influences. The findings indicate that all treatments exhibited increased microbial populations compared to the control. Notably, treatment 75% recommended potassium dose + 25% potassium from Biotite + OVPS 05 consistently demonstrated the highest microbial growth. The presence of KSB appeared crucial in enhancing bacterial and fungal populations. Additionally, enzymatic activities were significantly influenced by treatments, with 75% recommended potassium dose + 25% potassium from Biotite + OVPS 05 showing the highest dehydrogenase, alkaline phosphatase, and urease activities. These results suggest that the combination of KSB isolates and mineral potassium contributes to enhanced microbial populations and soil enzymatic activities, offering insights into sustainable agriculture practices that balance productivity and soil health. The study sheds light on the intricate relationships between microorganisms, nutrients, and soil biochemical processes, providing valuable guidance for future agricultural strategies.

Analysis of the Potassium-Solubilizing Priestia megaterium Strain NK851 and Its Potassium Feldspar-Binding Proteins.

Potassium-solubilizing bacteria are an important microbial group that play a critical role in releasing mineral potassium from potassium-containing minerals, e.g., potassium feldspar. Their application may reduce eutrophication caused by overused potassium fertilizers and facilitate plants to utilize environmental potassium. In this study, a high-efficiency potassium-solubilizing bacterium, named NK851, was isolated from the Astragalus sinicus rhizosphere soil. This bacterium can grow in the medium with potassium feldspar as the sole potassium source, releasing 157 mg/L and 222 mg/L potassium after 3 days and 5 days of incubation, respectively. 16S rDNA sequencing and cluster analysis showed that this strain belongs to Priestia megaterium. Genome sequencing further revealed that this strain has a genome length of 5,305,142 bp, encoding 5473 genes. Among them, abundant genes are related to potassium decomposition and utilization, e.g., the genes involved in adherence to mineral potassium, potassium release, and intracellular trafficking. Moreover, the strong potassium-releasing capacity of NK851 is not attributed to the acidic pH but is attributed to the extracellular potassium feldspar-binding proteins, such as the elongation factor TU and the enolase that contains potassium feldspar-binding cavities. This study provides new information for exploration of the bacterium-mediated potassium solubilization mechanisms.