Potassium Concentration Research Articles

The Adaptive Mechanism of Ginseng Rhizomes in Response to Habitat Changes

Panax ginseng, a perennial medicinal plant, utilizes its dried roots and rhizomes for medicinal purposes. Currently, in China, ginseng cultivation employs two methods: under-forest and farmland planting. These methods create distinct habitats, significantly influencing the ginseng’s rhizome morphology and, consequently, its economic value. In this study, two-year-old ginsengs were transplanted into farmland (TCG), a larch forest (TLCG) and a Quercus mongolica forest (TQCG) to analyze the differences in rhizome phenotypes caused by habitat changes. The results showed that there were significant differences in light intensity and the soil’s available phosphorus and potassium contents between farmland and forest environments. The differences in habitats led to different adaptability of the ginseng’s rhizome morphology. Compared with TCG, the rhizomes of TLCG and TQCG were significantly elongated by 48.36% and 67.34%, respectively. After the rhizomes’ elongation in TLCG and TQCG, there was an increase in indole-3-acetic acid (IAA) contents and a decrease in lignin contents. By analyzing the expression of key genes, we found that, compared with TCG, the expression of key enzymes of lignin biosynthesis genes such as PgCOMT and PgCCR4 were down-regulated. The difference in ginseng’s rhizome length is related to the signal transduction pathway of auxin and gibberellin. In addition, we preliminarily screened out transcription factors PgWRKY75, PgDIV, and PgbHLH93.1, which can actively respond to habitat changes and play important roles in the elongation of ginseng rhizomes. In summary, this study elucidates the phenotypic plasticity strategy of ginseng rhizomes in response to habitat changes and delineates the regulatory mechanism behind phenotypic adaptation, offering novel insights into ginseng’s morphogenesis.

Fiber morphological characteristics of bamboo Ferrocalamus strictus culms from different geographical distribution regions

The fiber index including fiber length, width, wall thickness and lumen diameter of Ferrocalamus strictus culms (1, 2, and ≥ 3 years) from Jinping, Mojiang and Lvchun counties of Yunnan Province was determined and the elemental content of the soil was also determined to analyze the fiber characteristics. The average relative fiber index measured for F. strictus culms were fiber length (1.30 mm), width (21.57 μm), slenderness ratio (60.79 μm), wall thickness (4.21 μm), lumen diameter (7.22 μm), and runkel ratio (1.22 μm), which belonged to the range of middle and long fibers. The fiber length increased with the culm age. The proportion of long fiber increased while short fibers decreased along with culm maturing. The fiber morphology did not show a specific trend with the culm height. Fiber length reached the maximum in the bottom portions of the culms. There is a correlation between fiber morphology and soil elements, the content of organic matter, total potassium, total sulfur, total aluminum, total zinc, total iron, total boron, alkali-hydrolyzed nitrogen and available silicon in the soil affects fiber morphology. The content of organic matter, total boron and alkali-hydrolyzed nitrogen in the soil from Mojiang County was largest. Comparatively, the culm fiber in Mojiang County had the best fiber index performance for utilization, since the greatest proportion of medium and long fibers and the optimal distribution of fiber length frequency was obtained from the culms in Mojiang County. This study can provide a theoretical basis for large-scale bamboo forest cultivation and the development and utilization of bamboo culm fiber.

Determination of phytochemical quality of leaves Vaccinium vitis-idaea L. and Vaccinium myrtillus L. from the polluted and non-polluted areas

Elemental composition of Vaccinium myrtillus L. and Vaccinium vitis-idaea L. has not been determined yet in detail. In our study, a scanning electron microscope coupled with an energy dispersive X-ray analyser (SEM–EDX) ensured the determination of 15 elements in the leaves of Vaccinium sp. growing in the control and the mine polluted locality. The soil elemental analyses showed a higher content of 11 elements from all determined in the mine-influenced samples. Elemental analyses of the control leaves showed the highest contents of all determined elements for V. vitis-idaea, except for carbon. The impact of pollution on V. myrtillus leaves caused significant increase in oxygen, natrium, magnesium, sulphur, chlorine, potassium and calcium content. The contents of carbon, nitrogen and silicon decreased substantially. In the case of the V. vitis-idaea leaves, the content of most of elements reduced, and in the case of six elements, even significantly. A significant increase was recorded for carbon, iron and copper. The effect of the environment has influenced the production of phytochemicals, assessed by HPLC–DAD. The production of flavonoids (hyperoside, isoquercetin) increased significantly in V. myrtillus and decreased to a detectable minimum in V. vitis-idaea. In the case of chlorogenic acid, arbutin and hydroquinone, their levels changed minimally in V. myrtillus, but significantly more in the V. vitis-idaea leaves. The importance of elemental analyses lies in detecting the presence of toxic elements or their harmful concentrations in plants that are the source of food or dietary supplements.

Biochar Organic Fertilizer Combined with Indigenous Microorganisms Enhances the Growth of Landscape Grass Cultivated in a Substrate Mixed with Iron Tailings and Mining Topsoil.

Iron tailings from the mining process occupy vast land areas and pose a significant ecological risk. In order to reuse iron tailings resources and carry out in situ ecological restoration of a mine, in this study, a medium of mixed iron tailings and mining topsoil (m:m = 3:1) was used to plant landscape grasses, including Lolium perenne L. (L. perenne), Pennisetum alopecuroides (L.) Spreng. (P. alopecuroides), Melilotus officinalis (L.) Lam. (M. officinalis), and Medicago sativa L. (M. sativa). Biochar and chicken manure were used as biochar organic fertilizers and indigenous microorganisms were isolated from the rhizosphere soil of tested grasses. They were applied to enhance landscape grass growth by regulating rhizosphere microbial communities and nutrient conditions. The results showed that the biochar organic fertilizers significantly promoted the growth of the four landscape grasses, notably P. alopecuroides, increasing plant height, root length, root weight, and leaf fresh weight by 169%, 60%, 211%, and 388%, respectively. Additionally, L. perenne exhibited the greatest height increase (10%) following the application of bacterial solutions. Moreover, indigenous bacterial solutions enhanced chlorophyll content and phenylalanine ammonia-lyase (PAL) activity, with P. alopecuroides showing the highest chlorophyll increase of 58% and M. sativa exhibiting a 30.58% rise in PAL activity. The biochar organic fertilizer also significantly elevated soluble protein content in P. alopecuroides and M. sativa by 195% and 152%, respectively. It also effectively enhanced peroxidase (POD) activity in Poaceae grasses by 120% to 160%. After adding indigenous microorganisms, the rhizosphere soil of the landscape grass showed the highest Shannon-Wiener diversity index, reaching 3.561. The rhizosphere soil of M. officinalis had the highest microbial richness, with a value of 39. Additionally, the addition of indigenous microorganisms increased the nitrogen, phosphorus, and potassium content of the four plants by 8-19%, 6-14%, and 8-18%, respectively. This study offers a new approach for managing mining waste and ecological restoration in mining areas.

Analysis of the composition and function of rhizosphere microbial communities in plants with tobacco bacterial wilt disease and healthy plants

ABSTRACT To explore the factors influencing the occurrence of bacterial wilt, the differences in the physicochemical properties, microbial community composition and function between rhizosphere soil of tobacco plants with bacterial wilt and healthy plants in the tobacco planting area of Fuzhou City, Jiangxi Province were analyzed and compared. The results showed that the rhizosphere soil of diseased tobacco exhibited significantly reduced levels of exchangeable potassium, water-soluble potassium, nitrate nitrogen, total nitrogen and pH, in comparison to the rhizosphere soil of healthy plants. Conversely, the available phosphorus content of the rhizosphere soil of diseased tobacco was significantly increased. The amount of Ralstonia solanacearum in soil was negatively correlated with pH, nitrate nitrogen and total nitrogen, and positively correlated with exchangeable potassium and water-soluble potassium. A total of 43 genera were significantly different between the two groups of rhizosphere soil, of which 24 genera were enriched in the rhizosphere of healthy plants, including Ideonella , Rhizophagus , Rhizobacter , Altererythrobacter and Ignavibacterium associated with plant disease resistance, Thermodesulfovibrio , Syntrophorhabdus , Syntrophus , Chlorobium , Hydrogenophaga and Limnohabitans associated with soil sulfur metabolism, as well as Ignavibacterium , Ideonella , Derxia and Azohydromonas associated with soil nitrogen cycling. Kyoto Encyclopedia of Genes and Genomes functional analysis of the unigenes obtained by metagenomic sequencing also showed that the differential unigenes were significantly enriched in the sulfur metabolism pathway. In addition, the rhizosphere soil of diseased tobacco plants exhibited a higher abundance of antibiotic-producing actinomycetes and an increased load of antibiotic resistance genes compared to that of healthy plants. In general, lower pH value, less content of nitrate nitrogen and total nitrogen, and more content of exchangeable potassium and water-soluble potassium could contribute to onset of bacterial wilt. Twenty-four genera, including Ideonella and Rhizophagus , may construct a healthy microecological network in the rhizosphere of tobacco plants. All these factors may interact with each other to control the development of bacterial wilt. This complicated interaction network needs to be explored further. IMPORTANCE Previous studies have mainly focused on the differences in microbial species composition between healthy and diseased soils, but the differences in microbial community functions between two types of soil have not been well characterized. In this study, soil samples in diseased and healthy plant rhizospheres were collected for physicochemical property testing and metagenomic sequencing. We focused on analyzing the differences in physicochemical properties and microbial community functions between these soils, as well as the correlation between these factors and pathogen content. The results of this study provide a theoretical basis for further understanding the occurrence of tobacco bacterial wilt in the field.

The effect of spironolactone versus eplerenone on blood pressure targets in resistant hypertension patients

Abstract Objective to evaluate different effects on blood pressure (BP) control in two treatment options spironolactone (SPIR) versus eplerenone (EPL) as an add-on therapy in resistant hypertensive (RAH) patients. Design and methods: We studied 208 patients with true RAH confirmed by the office and ambulatory BP monitoring (ABPM) despite the use of 3 antihypertensive medications including a calcium channel blocker, a blocker of the renin-angiotensin system, and a thiazide diuretic with maximally tolerated doses for at least 3 months. Patients were randomized into 2 groups throughout 12 weeks of once-daily treatment with SPIR (25–50 mg) or EPL (25-50 mg) in addition to their baseline triple-combination and then rotated with drugs. BP was measured in the office and by ABPM. Changes in laboratory tests were also studied. The predictive values of plasma aldosterone, active renin concentration (ARC), aldosterone-renin ratio (ARR), and serum potassium were analyzed to determine the antihypertensive response. Results There were no significant differences in the reduction of average office BP, average systolic 24-h, daytime, and nighttime BP by SPIR and EPL. SPIR reduced average diastolic 24-h BP by 7.3 mm Hg, diastolic daytime BP by 7.2 mm Hg, and diastolic nighttime BP by 7.5 mm Hg compared with a reduction of 5.6 mm Hg (P = 0.01), 5.6 mm Hg (P = 0.03) and 4.2 mm Hg (P = 0.0001) with EPL, respectively. Overall, 40.7 % RAH patients achieved targets of clinical BP and 24-h ABPM levels on SPIR and 33.3 % on EPL (Р = 0.002). After 12 weeks of treatment mean plasma potassium concentrations increased by 7.1 (P = 0.0001) on SPIR and by 5.0 % (Р = 0.0001) on EPL, but eGFR did not significantly change on the two drugs. Plasma aldosterone (β = 0.498, Р = 0.02) and ARC (β= -0.374, Р = 0.04) were predictors of the BP-lowering effect of SPIR and plasma aldosterone (β = 0.453, Р = 0.04) was a predictor of reduction BP for EPL in multivariate modeling. Breast pain or tenderness, changes in sex drive, and irregular menstrual cycles or spotting were more often by SPIR than by EPL (5.2 % vs 1.9 %, respectively, P = 0.04). Conclusions The greater antihypertensive effect of SPIR is related to aldosterone status, ARS level in resistant hypertension. EPL may be recommended for RAH patients who have high serum potassium levels that cannot tolerate spironolactone and for people with systolic resistant hypertension.

Effects of Microbial Organic Fertilizer, Microbial Inoculant, and Quicklime on Soil Microbial Community Composition in Pepper (Capsicum annuum L.) Continuous Cropping System

The additions of microbial organic fertilizer (MOF), a microbial inoculant (MI), and quicklime (Q) are considered to be sustainable practices to restore land that has been damaged by continuous cropping of pepper (Capsicum annuum L.). However, the combined effects of these three additives on pepper yield, soil chemical properties, and soil microbial communities were unclear. The experimental design consists of 13 treatment groups: the untreated soil (control); soil amended solely with three treatments for each of MOF (1875–5625 kg ha−1), MI (150–450 mL plant−1), and Q (1500–4500 kg ha−1); and soil amended with combinations of MOF, MI, and Q at three comparable concentrations. A significant increase in pepper fruit diameter, length, yield, and soil available nitrogen, phosphorus, and potassium contents occurs upon exclusive and combined applications of MOF, MI, and Q. Pepper yield was greatest (29.89% more than control values) in the combined treatment with concentrations of 1875 kg ha−1 MOF, 150 mL plant−1 MI, and 1500 kg ha−1 Q. The application of Q increased soil pH and reduced soil–fungal richness. The application of MOF, MI, and Q increased the relative abundance of bacterial genera and the complexity of bacterial and fungal co-occurrence networks compared with control levels. The combined application of MOF, MI, and Q resulted in the greatest microbial network complexity. A Mantel test revealed the key role of soil available nitrogen content and bacterial diversity in the regulation of pepper growth and yield. We conclude that the combined application of MOF, MI, and Q improves soil nutrient availability and modifies soil microbial community composition, significantly promoting plant growth and pepper yield during continuous cultivation.

Leaf nutrient basis for the differentiation of photosynthetic traits between subtropical evergreen and deciduous trees.

Compared to evergreens, deciduous tree species usually have higher photosynthetic efficiency to complete vegetative and reproductive growth in a shorter growing season. However, the nutrient basis for the differentiation of photosynthesis functional traits between evergreen and deciduous tree species has not yet been clarified. Thirty evergreen and twenty deciduous angiosperm tree species from a subtropical common garden were compared in terms of photosynthetic traits and leaf nutrients. Generally, their differences in area-based photosynthetic capacity were uncorrelated with area-based leaf nutrient content but were caused by the fraction of nitrogen allocated to photosynthetic components. By comparison, the differences in mass-based photosynthetic capacity were more correlated with leaf nitrogen content than leaf phosphorus and potassium content. Convergence in phosphorus and potassium constraints to photosynthesis occurred in deciduous tree species but not in evergreen tree species. Furthermore, leaf C/N ratio played a more significant role than leaf mass per area in determining the differentiation of photosynthetic traits between evergreen and deciduous groups. Our findings provide insight into the nutrient basis for photosynthetic carbon gain and functional strategies across trees species.

Proximate, Mineral, Amino Acid Composition, and Bioactive Properties of Dough Meals Supplemented with African Walnut Flour

This study investigated the impact of African walnut flour supplementation on the nutritional and bioactive properties of dough meals formulated with varying proportions of plantain flour. The proximate composition, mineral content, amino acid profile, color characteristics, antioxidant and anti-diabetic properties were analyzed for five different formulations: 100% plantain flour (P100), 95% plantain flour with 5% African walnut flour (PAW95), 90% plantain flour with 10% African walnut flour (PAW90), 85% plantain flour with 15% African walnut flour (PAW85), and 80% plantain flour with 20% African walnut flour (PAW80). The proximate analysis revealed significant variations, with moisture content ranging from 53.71% to 71.89%, ash content from 0.77% to 1.28%, and protein content from 3.38% to 11.14%. Notably, PAW80 showed the highest protein content. Mineral analysis showed that calcium, potassium, and magnesium levels varied significantly across the samples, with the highest calcium content observed in PAW80 (32.55 mg/kg) and the highest potassium content in PAW95 (47.80 mg/kg). Amino acid analysis indicated that essential amino acids, particularly leucine, valine, and lysine, were present in higher concentrations in the supplemented samples compared to P100. Antioxidant assays indicated that PAW80 had the highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) (67.22%) and hydroxyl (73.66%) free radical scavenging activities. The in vitro anti-diabetic assays revealed that α-amylase and α-glucosidase inhibitory activities were enhanced with higher walnut flour supplementation. These findings suggest that African walnut flour can significantly enhance the nutritional quality and bioactive properties of plantain-based dough meals, and thus make it a functional food with potential health benefits.

Actinobacteria derived from soybean/corn intercropping influence the subsequent wheat

Soil legacy effects, especially soil bacterial legacy effects, influence growth, fitness and nutrient acquisition in sequential cropping systems. To date, mechanisms underlying soil bacterial legacy influences on subsequent crops remain largely unknown. In this study, we employed soybean monoculture (S), corn monoculture (C), and soybean/corn intercropping (SC) to study soil legacy effects on the growth and nutrient acquisition of wheat. In these tests, S, C and SC drove establishment of distinctive soil bacterial communities, with higher abundances of Actinobacteria and Proteobacteria taxa observed in SC plots than in S and C treatments. Variation among soil bacterial communities was associated with functional shifts in nitrogen cycling in SC treatment compared to other treatments（C and Control）. Soil legacy effects in turn may contribute to growth, nutrient acquisition and grain production in wheat crops planted in rotations. Pot assay suggest that soil microorganism of SC treatment significantly increased the plant height of wheat by 15.1 % and 18.7 %, the shoot biomass by 50.7 % and 62.7 %, the nitrogen content by 76.0 % and 94.9 %, the phosphorus content by 80.3 % and 75.9 %, and the potassium content by 64.0 % and 83.7 % by compared with C and S. Actinobacteria taxa collections further promote nutrient acquisition of wheat. Taken together, our observations from field plots and manipulation of specific bacterial taxa revealed novel soil bacterial legacy effects of previously reared crops on subsequent crops. These new insights open avenues for using soil legacy effects for positive impacts in crop rotation systems.

Solid-to-gas phase transition kinetics of diverse potassium occurrence forms during biomass pellet combustion: Time-resolved detection and multi-step modeling

The solid-to-gas phase transition of potassium during biomass combustion significantly impacts ash-related issues in bioenergy systems, affecting operational efficiency and equipment longevity. However, the specific mechanisms and kinetics of this transition process remain inadequately understood. This work investigates the time-resolved transition of solid-phase potassium to the gas phase during the combustion of rice husk and wheat straw pellets, combining experimental measurements with theoretical modeling. Tunable diode laser absorption spectroscopy (TDLAS) was employed to measure atomic potassium concentrations 15 mm above burning pellets tray, where gas-phase equilibrium is approached. Key combustion characteristics including thermogravimetric profiles, spectral radiation, and temperature were simultaneously monitored. A novel multi-step model was developed to describe the transition of different forms of solid-phase potassium (organic, exchangeable, and inorganic) to the gas phase. This model integrates TDLAS measurements, observed combustion characteristics, and biomass physicochemical properties. Thermodynamic equilibrium calculations were used to estimate the atomic potassium fraction from total gaseous potassium. The results showed that the solid-to-gas phase transition of organic potassium synchronizes with volatiles release. In contrast, the maximum emission rates of inorganic and exchangeable potassium occurred at the onset of char combustion. The developed model agrees well with the online detection experiments and were further validated by offline ICP analysis of residual ash. While not directly simulating gas-solid interface reactions near the particle surface, this work lays groundwork for future multi-scale modeling of particle-laden flows and reactor-scale phenomena in biomass combustion systems.

The effect of extracellular potassium concentration on the oscillation frequency of the pacemaker nucleus in the weakly electric fish Apteronotus leptorhynchus.

The weakly electric brown ghost knifefish (Apteronotus leptorhynchus) exhibits a pronounced sexual dimorphism in its electric behavior-males discharge at higher frequencies than females, with little overlap between the sexes. The frequency of these electric organ discharges is controlled by the frequency of the synchronized oscillations of the medullary pacemaker nucleus. Previous studies have suggested that sex-specific differences in the morphology and gene expression pattern of the astrocytic syncytium that envelopes the pacemaking neural network cause differences in its capacity to buffer the extracellular concentration of K+. This change in the K+ buffering capacity affects the K+ equilibrium potential of the neurons constituting the neural network, which in turn modulates the frequency of the pacemaker nucleus. In the present study, we have tested a critical element of this hypothesis by examining whether, and how, changes in the extracellular K+ concentration influence the frequency of the pacemaker nucleus oscillations. By using an in vitro preparation of the pacemaker nucleus, the results of this investigation demonstrate that exposure of this nucleus to acutely increased/decreased concentrations of K+ in the perfusate (while maintaining osmolarity) leads to concentration-dependent increases/decreases in the frequency of the synchronized oscillations generated by the pacemaker nucleus.

Biofertilizers: A sustainable strategy for enhancing physical, chemical, and biological properties of soil

A biofertilizer is a biologically derived substance that can enhance soil fertility. It is beneficial for enhancing soil fertility by introducing microorganisms that produce organic nutrients and perhaps decreasing plant illnesses. An extensive review was done to examine the efficacy of several biofertilizers in improving soil properties, including their physical, chemical, and biological characteristics. The secondary data and material for the article were gathered from a variety of sources, including government reports, published research papers, reports from various organizations, and pertinent websites that were examined and their conclusions presented. Although biofertilizers have proven to be a very sustainable method for improving soil quality and increasing crop output, there is a lack of extensive research on their effects on soil’s physical, chemical, and biological aspects. This study aims to offer a comprehensive understanding of various biofertilizers and their effects. This investigation indicated that biofertilizers such as Nitrogen-fixing bacteria, phosphate solubilizers, and potassium solubilizers help to increase NPK content in the soil leading to an increase in the productivity of soil. Moreover, biofertilizers help to enhance soil physical properties (soil bulk density, soil moisture, soil temperature, and soil color), chemical properties (soil pH, soil nitrogen content, soil phosphorus content, soil potassium content, and soil organic carbon content), and chemical properties (population of bacteria, fungi, and actinomycetes). Overall, by overcoming the challenges with biofertilizers in agriculture, we can attain agricultural sustainability.

Effect of Castor Transplanting and Different Organic Manures on Nutrient Content, Uptake and Soil Fertility Status after Harvest of Castor (Ricinus communis L.) under North Gujarat Agro Climatic Conditions

An attempt was made to investigate the effect of castor transplanting and different organic manures on content, uptake and soil fertility status after harvest of castor (Ricinus communis L.) under North Gujarat agro climatic conditions. The field experiment comprised of four levels of age of seedling (A1: Two weeks old seedling, A2: Three weeks old seedling, A3: Four weeks old seedling and A4: Normal sowing) and four levels of source of manures (S1: No compost, S2: Vermicompost, S3: FYM and S4: Castor shell compost) laid out in randomized block design with factorial concept with three replication. Castor variety GCH 8 was used as a test crop. The result indicated that Nitrogen, phosphorus, potassium and sulphur content in castor seed did not differed significantly due to different age of seedling and different source of manures. But uptake of nitrogen, phosphorus, potassium and sulphur were significantly higher under treatment A4 (Normal sowing) and S4 (Castor shell compost). The available nitrogen, phosphorus, potash and sulphur in soil were unaffected due to age of seedling and source of manures. However, organic carbon was found significantly higher (0.204%) with treatment S4 (Castor shell compost). Interaction effect of age of seedling and source of manures exhibited significant effect on content of sulphur and uptake of nitrogen, phosphorus, potassium as well as sulphur.

Wood-Based Biochar Ratio Used for Partial Peat Replacement in Growing Media for Antirrhinum majus Pot Production

Biochar has been promoted mostly as a soil supplement that improves plant growth/yield and to a lesser extent as a growing medium component. The alarmed situation for peat substitution in growing medium renders biochar as a promising substitute for current research. In this study, biochar derived by wood-based materials was evaluated at different ratios (0, 5, 10, 15, and 20% v/v) for peat partial substitution for Antirrhinum majus pot production. Biochar had increased potassium content and pH, which affected the growing media properties (total pores space and water filled capacity) and decreased nitrogen and phosphorus content in the media. Adding ≥15% biochar increased plant height and decreased flowering, but no effect was observed on plant biomass produced. The presence of biochar increased the total phenols and flavanols content and antioxidant capacity, with greater effects at the higher biochar rates used. This resulted in lipid peroxidation and an increase in hydrogen peroxide content, causing oxidative stress. Potassium and magnesium accumulated more but nitrogen and phosphorus were accumulated less in snapdragon leaves. Biochar at 10% can be considered as a successful candidate to partially substitute peat, and efforts to improve growing media characteristics are required for A. majus pot production.

Ecological Capacity and Bioenergy Potential of Agrocenoses as a Way of Sustainable Agriculture

Background: Calculation of bioenergy potential and ecological capacity are promising methods for assessing the state of an agro-landscape, allowing us to promptly respond to changes in its sustainability. The article presents the results of soil research and calculation of bioenergy potential of the farm territory in the zone of dry steppe on chestnut soils. Methods: Assessment of anthropogenic load on agricultural landscape is based on ecological standards and point system of relative fertility. The determination of the ecological capacity by BEPT of an agrocenosis occupied by winter wheat and sunflower was carried out according to the method of V.M. Volodin, R.F. Eremina, N.F. Mikhailova. Determination of erosion and geomorphological characteristics of the research object was carried out using geoinformation technologies. The basis for creation of digital elevation model (DEM) is the data of radar survey of the Earth surface (SRTM4). Result: Soils of the research object have low and average humus content. Nitrogen level in the soil varies from very low to good; nitrogen availability in the fields is average. Provision with mobile phosphorus is average. Soil potassium content is mostly high. As a result of calculations, it was found that in the conditions of the dry steppe zone, the bioenergy potential of the agrolandscape area occupied by winter wheat is 2735.72 GJ/ha, sunflower-2647.4 GJ/ha. At the same time, the ecological capacity of the field occupied by winter wheat is 2764.6 GJ/ha and sunflower-2676.8 GJ/h.

Nutrient Stoichiometry and Tree Development: Insights from a 5-Year Study on Catalpa bungei Fertilization

Short-term fertilization may provide limited improvements in tree growth and demonstrate suboptimal fertilizer efficiency; however, its benefits often fall short of expectations. Unfortunately, research addressing the sustained impacts of prolonged fertilization (e.g., beyond five years) on trees’ developmental dynamics and productivity remains relatively scarce. This study focused on a 7-year-old Catalpa bungei plantation located in Jinan City, Shandong Province, China. The study employed two fertilization techniques: hole fertilization (HF) and integrated water and fertilizer application (WF), with a no-fertilization treatment serving as the control (CK). The findings revealed that the WF significantly enhanced stand productivity. When comparing the different treatments, the productivity of WF stands demonstrated a remarkable increase of 39.7% compared to HF stands and 55.1% compared to CK stands. After five years of fertilization, the stands treated with WF exhibited a significant increase in volume accumulation, reaching 112.36 m3·hm−2. Additionally, the productivity of these WF-fertilized stands achieved an impressive 41.75 m3·hm−2·a−1. Fertilization notably enhanced the nitrogen content in the leaves and fine roots of C. bungei, as well as the potassium content in the coarse roots. These nutrients were found to be more concentrated in the corresponding organs within the WF stands. Over the entire growth cycle, there was a substantial consumption of key nutrients, with leaf nitrogen, phosphorus, and potassium contents decreasing by 30.5%, 18.8%, and 47.3%, respectively. Similarly, the coarse root potassium and fine root phosphorus content decreased by 24.7% and 24.4%, respectively. The enhancement in leaf nitrogen content following fertilization significantly contributed to increases in tree height, breast height diameter (DBH), and individual tree volume. Similarly, the enrichment of potassium in the branches and coarse roots was associated with improvements in DBH and tree volume. To maximize forest stand productivity, the WF fertilization method demonstrated superior results compared to HF. Therefore, WF should be prioritized in future fertilization experiments for C. bungei.

Assessment and Delineation of GPS-GIS Based Soil Fertility Maps of Instructional Farm, Malegaon Tehsil Baramati

The present investigation was conducted in the year 2023-24 at division of Soil Science, Dr. Sharadchandra Pawar College of Agriculture, Baramati with an objectives to assess the soil available nutrient status and delineation of GIS based maps of soil available nutrients. Using Arc-GIS 10, Version 10.8, fertility maps of the available macro nutrients were created. The area under the Instructional Farm had soil pH ranged from 7.11 to 8.32, categorized into the slightly alkaline to moderately alkaline categories while the EC varied from 0.21 to 1.99 dSm-1, indicating that most of the soils were non-saline. The soil's organic carbon and calcium carbonate contents ranged from 0.21 to 0.97 per cent and 1.50 to 19.75 per cent and they were classified into low to high and low to very high categories respectively. In the Instructional Farm, the ranges of available nitrogen, phosphorus and potassium content were 85.50 to 360.75, 23.29 to 80.08 and 202.5 to 968.68 kg ha-1 respectively. The Instructional Farm soils had very low to moderate levels of available nitrogen, moderately high to very high levels of available phosphorus and moderately high to very high levels of available potassium. The implementation of GPS-GIS-based techniques for soil sampling represents a significant advancement that will allow researchers and institute officials to track changes in soil fertility over the years. The soil fertility maps created for the Instructional Farm will be invaluable for establishing a scientifically sound fertilization schedule.

Gold Mineralization at the Syenite-Hosted Anwangshan Gold Deposit, Western Qinling Orogen, Central China

The Anwangshan gold deposit is located in the northwestern part of the Fengtai Basin, Western Qinling Orogen (WQO). The gold ore is hosted within quartz syenite and its contact zone. The U–Pb weighted mean age of the quartz syenite is 231 ± 1.8 Ma. It is characterized by high potassium (K2O = 10.13%, K2O/Na2O > 1) and high magnesium (Mg# = 55.31 to 72.78) content, enriched in large ion lithophile elements (Th, U, and Ba) and light rare earth elements (LREE), with a typical “TNT” (Ti, Nb, and Ta) deficiency. The geochemical features and Hf isotope compositions (εHf(t) = −6.68 to +2.25) suggest that the quartz syenite would form from partial melting of an enriched lithospheric mantle under an extensional setting. Three generations of gold mineralization have been identified, including the quartz–sericite–pyrite (Py1) stage I, the quartz–pyrite (Py2)–polymetallic sulfide–early calcite stage II, and the epidote–late calcite stage III. In situ sulfur isotope analysis of pyrite shows that Py1 (δ34S = −1.1 to +3.8‰) possesses mantle sulfur characteristics. However, Py2 has totally different δ34S (+5.1 to +6.7‰), which lies between the typical orogenic gold deposits in the WQO (δ34S = +8 to +12‰) and mantle sulfur. This suggests a mixed source of metamorphosed sediments and magmatic sulfur during stage II gold mineralization. The fluid inclusions in auriferous quartz have three different types, including the liquid-rich phase type, pure (gas or liquid)-phase type, and daughter-minerals-bearing phase type. Multiple-stage fluid inclusions indicate that the ore fluids are medium-temperature (concentrated at 220 to 270 °C), medium-salinity (7.85 to 13.80% NaCleq) CO2–H2O–NaCl systems. The salinity is quite different from typical orogenic gold deposits in WQO and worldwide, and this is more likely to be a mixture of magmatic and metamorphic fluids as well. In summary, the quartz syenite should have not only a spatio-temporal but also a genetical relationship with the Anwangshan gold deposit. It could provide most of the gold and ore fluids at the first stage, with metamorphic fluids and/or gold joining in during the later stages.

Impact of Boiling on Composition of Oven-Dried Curcuma Longa Linn Rhizomes

The effect of boiling Curcuma longa Linn rhizomes prior to oven drying on its proximate, mineral and phytochemical composition was studied. Fresh turmeric rhizomes were sliced to 5 mm thickness and then divided into two parts. The first part was oven dried directly while the second part was boiled prior to oven drying. Both products were then pulverised and subjected to laboratory analysis following standard procedures of AOAC and spectrometry. Boiling had an impact on the proximate composition as there were significant (P<0.05) reductions in ether extract, crude fibre and crude protein. Sodium, calcium, potassium and phosphorus contents were significantly reduced with a significant increase in levels of magnesium, zinc and iron (P<0.05). Significant reductions in phytochemicals due to boiling prior to oven drying were also recorded (P<0.05). This experiment therefore shows that boiling Curcuma longa Linn rhizomes prior to oven drying could be of pharmacological importance.