Black Clay Research Articles

Mechanisms of microbial diversity modulation of mineral black clay to achieve ecological restoration of open-pit mine dump

The harsh climatic conditions and severe scarcity of surface soil present significant challenges to ecological restoration in open-pit mine dumps within China's type II plant cold resistance zone. To address the topsoil shortage, mineral black clay was used to create synthetic soil. This study explored the application of an ecological restoration bacteria (ERB) consortium to accelerate the ecological restoration of synthetic soil-covered areas by enhancing soil ecosystem construction. The results demonstrated that ERB significantly influenced the native bacterial community structure in mixed black clay. Specifically, ERB disrupted the inhibitory effects of the Actinobacterota phylum on the development of native bacterial diversity, leading to an increase in unclassified_o_Solirubrobacterales sp., norank_f_norank_o_norank_c_KD4-96 sp., Sphingomonas sp., Luteitalea sp., norank_f_Vicinamibacteraceae sp., and other aerobic and anaerobic bacteria. These alterations in soil microbial structure directly impacted soil composition and vegetation diversity. The plant diversity survey and metabolomics analysis revealed that the reduction of harmful substances, such as HPED, HODE, and HOME, in black clay soil improved the growth and distribution of Salsola collina Pall. and Medicago sativa L. This increase facilitated the cycling of key nutrients, such as nitrogen (N) and phosphorus (P), and promoted the establishment of symbiotic relationships between plants, microorganisms, and soil. Ultimately, the ecological remediation of the synthetic soil was achieved through the synergistic effects of ERB, which included the degradation of inhibitory soil components, enhanced nutrient consumption by microbiota and plants, and the overall promotion of ecosystem stability in the reclamation area.

Effect of Integrated Nutrient Management on Nutrient Availability Dynamics in Laboratory-incubated Black Clay Soil

Nutrient release in different soils is a dynamic process influenced by a multitude of factors, including soil texture, structure, organic matter content, pH, microbial activity, and nutrient management practices. An incubation study was conducted to study the nutrient availability and their release at different days after incubation through nutrient management practices. The results of the study revealed that at 15 DAI, available nitrogen and its fraction, available sulphur were recorded higher in the treatment receiving soil test based NPK, at 30 DAI in the treatment with integrated application 100% RDF, FYM and biofertilizers, at 45 and 60 DAI treatment receiving 75% soil test based NPK, FYM and biofertilizers. Available phosphorus recorded content recorded higher in the treatment with integrated application 100% RDF, FYM and biofertilizers and it continued to increase upto 45 DAI and their after its content decreased slightly to 60 DAI. Similar to available phosphorus, available potassium content also recorded higher in the treatment with integrated application 100% RDF, FYM and biofertilizers and it continued to increase upto 60 DAI. Treatments receiving sole inorganic fertilizers exhibited early decline in nutrient content whereas integrated treatments maintained the nutrient availability more than the sole inorganic fertilizers applied treatments.

Effects of microplastic contamination on the hydraulic, water retention, and desiccation crack properties of a natural clay exposed to leachate

Microplastic (MP) can significantly affect soil behaviour and the ecosystem. This paper presents an experimental study to investigate the effects of MP contamination and leachate exposure on the desiccation cracks, hydraulic conductivity, and water retention properties of the natural black clay. The leachate was from a landfill in Australia. The black clay was incorporated with up to 2.0% MPs by weight (w/w) with diverse dimensions and mixed with water/leachate. The measured properties include saturated hydraulic conductivity (ksat), soil-water characteristic curves, moisture evaporation rates, and crack intensity factors. The results suggest that the inclusion of MPs significantly increases ksat, and this increase is more obvious for soils with larger dimensions and contents of MPs, e.g., ksat of the black clay with 2.0% of 500 μm MP increases significantly by 206% (p < 0.05). The black clay exposed to leachate exhibits a slight increase in ksat due to the low viscosity of leachate. The existence of MPs decreases the residual moisture contents and air-entry pressures, and so does the water retention capacity (v/v %) of the black clay. The exposure to leachate increases the air-entry pressures by 6.0%–15.8% of the clay. The evaporation rates increase with the dimensions and concentrations of MPs. The highest evaporation rate (0.96 g/h) can be observed in samples exposed to 2.0% 500 μm MP with water addition. For all samples, the crack intensity factors increase when MP content is between 0.2% and 1.0% and decreases slightly after that. After being exposed to leachate, the evaporation rates and crack intensity factors of the black clay are decreased by 2.4%–12.6% and 3.6%–13.7%, respectively.

Facile synthesis of a recyclable multifunctional magnetic adsorbent prepared from H2O2-modified carbon clay/rice flour polymer/Fe3O4 nanoparticles interface for effective removal of ibuprofen

BackgroundThe combination between magnetite nanoparticles with natural carbohydrate polymers and aluminosilicates is recommended to be a positive strategy in the design of a new type of low-cost, high–efficiency, and eco-friendly magnetic adsorbents for decontamination of toxic pharmaceutical compounds from water. In particular, ibuprofen (IBP) is found to be one of the common drugs detected in water bodies, which is a suggestively alarming state. MethodsA fresh sample of gossan (iron-bearing weathered product) was used in the fabrication of magnetite nanoparticles (MNPs) to be used in the decoration of a bio-composite prepared from H2O2-activated black clay (BC) and biodegradable rice flour (RF) interface. The as-synthesized magnetic biosorbent (BC/RF/MNPs) was characterized by FTIR, FESEM, TEM, XRD, DSC, and TGA techniques and employed in the remediation of ibuprofen at pH 7.0 and temperatures of 25, 40, and 50°C. The adsorption results were fitted to kinetics, traditional isotherms, and statistical physical models to better understand the interaction between IBP and BC/RF/MNPs adsorbent. Significant findingThe pseudo-second-order (PSO) and Freundlich equations described the IBP adsorption system. Monolayer and double-layer advanced statistical physics models were employed to analyze the geometry and interactions mechanism at the molecular scale. The double-layer model showed the best-fitting results, and thus, its steric and energetic parameters and thermodynamic functions were explained. The number of the removed IBP molecules per site (steric n parameter) ranged from 0.55 to 0.84 suggesting the involvement of parallel and non-parallel orientations in the removal process. The adsorption capacity at saturation (Qsat) increased from 45.73 to 67.90mg/g at 25 - 50 ºC signifying endothermic interactions. The adsorption energy ranged from 0.42 to 3.42kJ/mol reflecting the physical interactions between IBP and BC/RF/MNPs. Thermodynamic functions suggested the endothermic and spontaneous nature of the IBP adsorption process. Adsorption/desorption results suggested the high stability and economic benefit of BC/RF/MNPs sorbent.

New Hominin calvaria discovery from Grenzbank Layer of Sangiran Dome (Java, Indonesia): The last archaic Homo erectus lived in Java

Sangiran Dome in Central Java, Indonesia, is the most significant hominin site in Island Southeast Asia. Up to now, there are more than a hundred of Homo erectus individuals recovered from the site, and the most recent finding is an unpublished posterior part of Bjg 1602 skullcap, discovered by a local people in 2016 from the surface of Kali (River) Bojong, out of stratigraphical context. But, based on the hard concretion well attached on the fossil, consists of coarse conglomeratic sand and pisoid-limestones – defined for the first time by G.H.R. von Koenigswald as the grenzbank layer – this skullcap is interpreted originally from this layer. Stratigraphically, the layer is situated between the black clay of Pucangan Formation of Lower Pleistocene and the fluvio-volcanic sands of Kabuh Formation of Middle Pleistocene. Thus, this layer was deposited on the Sangiran site some 0.9–0.8 ma, which is the minimal age of the skull respectively. This paper aims to identify the possibly position of the specimen and its context to the Homo erectus evolution in Java. The specimen was analysed by applying the morphological and metrical descriptions of the external characters. Then, a comparative study to other African (n=5), Asian (n=7), and Javan Homo erectus (n=23) was conducted by using univariate and bivariate statistical analysis, in order to place the specimen into evolutionary perspective. The result shows that Bjg 1602 skullcap is very closed in morphology and size to the robust Sangiran 4 skullcap (firstly known as Pithecanthropus robustus), which is one of the robust Homo erectus members from the Early Pleistocene between 1.6 to 1.2 ma. Thus, it could be concluded that the specimen of Bjg 1602 represents the last survival of robust Homo erectus in Java during the early of Middle Pleistocene, some 0.9 ma.

An Integrated Approach to Evaluating Crop Water Requirements and Irrigation Schedule for Optimizing Furrow Irrigation Design Parameters in Kurnool District, India

In Kurnool district, due to the hot, arid climatic conditions, proper study of crop evapotranspiration and its effect on crop water demand for various crops is an extremely important issue. More focus will be given to the design and development of surface irrigation systems based mostly on furrow irrigation, as the rainfall pattern for this district was irregular in 2005. The crop water requirement and furrow irrigation design parameters for optimising the beneficial utilisation of available water resources and field performances are studied in this research. Some major crops, such as cotton, sugarcane, sorghum, maize, and sunflower, are considered when adopting a suitable furrow irrigation system for soil conditions of the types black clay, red loamy, and medium loam. The reference crop evapotranspiration was estimated for 2005 based on the Penman–Monteith equation as per FAO guidelines by the CROPWAT 8.0 model. Crop Water Requirement (CWR), Net Irrigation Requirement (NIR), and Gross Irrigation Requirement (GIR) were determined for available climatic and soil conditions. Soil surface characteristics were studied using AQUACROP 6.1 and compared with CROPWAT 8.0 for model accuracy. Various conservative and non-conservative crop characteristics were studied under limited set conditions, and correlation equations were developed between different parameters. Moreover, different furrow irrigation design parameters were considered by FURDEV (a module of the SURDEV model) for three modes of operation (i.e., fixed flow, cutback flow, and tailwater reuse method) under modified SCS (Soil Conservation Service) families of soil infiltration characteristics. NIR values were 200 mm, 1423.2 mm, 220 mm, 150 mm, and 150 mm for cotton, sugarcane, maize, sorghum, and sunflower, respectively. A maximum significant dry yield was observed for maize (13.586 tonnes/ha). Additionally, the maximum application efficiency and storage efficiency were obtained at 95.5% for sorghum and 99.3% for sunflower, which would be a beneficial outcome of this research. In general, the results of this research might be very effective for the irrigation authority of Kurnool District to plan suitable approaches for designing and developing proper water management systems.

Pre-Extension Demonstration of Improved Durum Wheat Varieties in Growing Areas of Amhara and Oromia Regions of Ethiopia

In Ethiopia Durum wheat has been traditionally grown on heavy black clay (vertisols) on the residual moisture and recently being grown on light soils under rainfed conditions and it is consumed as leavened bread, common bread, macaroni, spaghetti, biscuits, and pastries. The national average yield is low because of the use of unimproved local cultivars, abiotic and biotic stresses. This research activity was conducted to create demand and awareness on the availability of the newly released varieties and evaluate the performance of the variety under farmers’ condition for further wider scaling up of the technology. The study went further to evaluate the preference of farmers concerning the demonstrated technology. Totally, fifty target farmers were selected for the research from ten kebeles of selected Districts. Training was provided for farmers, development agent and District experts. The newly released durum wheat varieties were planted on plots of 10 meter by 10 meter at Farmers’ Training Center and on 0.125 hectare of land on farmers’ field according to the recommended rate of fertilizer 100 kilo gram per hectare NPS and 150 kilo gram Urea with seed rate of 100 kilo gram per hectare. The results indicated that the highest average yield 3.5 tons per hectare was obtained from Utuba variety at Gelan Arabsa District of Sheger City. Utuba variety was preferred because of its higher yield, big grain seed size, heavy spike, market preference, good tillering capacity and palatable straw for animal feed while Tesfaye variety was preferred first by its disease resistance. Based on the findings, it is recommended that promotion of improved durum wheat varieties can contribute to durum wheat production and productivity improvement.

Accessibility and effects of binder types on the physical and energetic properties of ecological coal

The objective of this paper was to determine the effects of binders on the physical and energetic properties of briquettes as well as their accessibility. Proximate analysis and investigation on binder cost on local market were conducted. The results show that the addition of binder increases the durability and density, but decreases the LHV of briquettes. However, when the LHV of the binder is higher than that of the biomass used for briquette making, the LHV will increase. Among the binders used, cassava starch contains more LHV (19.082 ± 0.381 MJ/kg), followed by cow dung (17.088 ± 0.274 MJ/kg), arabic gum (16.015 ± 0.631 MJ/kg), bark of Grewia bicolor comes last with 14.020 ± 0.272 MJ/kg, and black clay does not contain energy. For a piece of briquette which weighs 20 g, bark of G. bicolor gives a better hardness with a crushing limit load of 22 kg, followed by arabic gum with 19.5 kg, and cow dung with 14 kg. Similarly, bark of G. bicolor gives the higher density, followed by arabic gum. A kg of gum arabic, G. bicolor and starch costs between US$ 1.60 and 3.17. It is important to afforest the plant species that produce binders.

An engineering-geological study of rock soils and the products of their fracture zones (Albazinskoe deposit, north Khabarovsk Krai)

Background. The results of an engineering-geological study of rock soils and the products of their fault zones are considered on the example of samples selected in the sides of the Albazinskoe gold-bearing deposit located in the north of the Khabarovsk Krai.Aim. To develop and implement a methodological approach, which includes laboratory determinations of the velocity of propagation of longitudinal seismic waves (“seismic speed”) using a “Pulsar-2.2” unit (methods of continuous and through sounding), as well as density, porosity and water absorption determinations along with obtaining information about the types of microstructure and microtexture, the mineral composition and mineral alteration features under the influence of metamorphism (using petrographical thin sections).Materials and methods. For the collected rock soil samples the relationship between seismic velocity and physical properties indicators was evaluated (R-type cluster analysis programme). The products of fractural zones were studied in a laboratory according to a specially-developed methodological approach: extended (black clay) and reduced (crushed stone formations with debris). The microelement composition of the clay and gravel of argillites was determined for the first time, and the level of their pollution by toxic microelements (Zc index) was evaluated.Results. On the basis of quantitative assessment of the relationship between indicators of rocky soils various properties identified using the cluster analysis program, an “anomalous” conclusion is obtained about the absence of the rock soil density effect on seismic properties, which can be explained by the textural and structural features, as well as by mineral composition and the consequences of metamorphism (cataclastic and blastogenetic features recorded on the microscale in thin sections).Conclusion. The proposed methodological approach can be recommended for further studies of seismic, strength and physical properties of rocky soils during seismological and engineering-seismological studies of various territories.

A COMPARATIVE STUDY ON THE EFFECT OF SISAL FIBRE AND WASTE PLASTIC STRIPS IN STRUCTURAL STRENGTH IMPROVEMENT OF TROPICAL BLACK CLAY

A study on the effect of sisal fibre and waste plastic strips on tropical black clay (also called Black cotton soil, BCS) was carried out. Tests piloted on the natural and treated soil consist of California bearing ratio (CBR), Atterberg limits and compaction for different percentages inclusion of sisal fibre (0, 0.5, 1, 1.5 and 2%) and waste plastic strips (0, 0.5, 1, 1.5 and 2%) by dry weight of soil. Results obtained showed that the liquid limit of BCS initially fluctuated between 43.4% and 55.9% at 1% sisal fibre content, then dropped to 49.4% at 2% sisal fibre content. In the case soil treated with waste plastic strips, liquid values increased from 43.4% for the natural soil to a highest value of 58% at 1% waste plastic strips and thereafter decreased to 49.15% at 2% waste plastic strips content. Plastic limit for both BCS-sisal fibre/ waste plastic strips initially decreased from its natural value of 25.78 to 15.55 and 14.77% when treated with sisal fibre and waste plastic strips respectively at 0.5% admixtures content. In the case of plasticity index, values initially increase from its natural value of 17.66% to peak values of 35.39 and 43.23% for sisal fibre and waste plastic strips treated soil respectively, and thereafter decreased. Maximum dry density (MDD) initially increased from 1.55 mg/m3 at 0%, to 1.60 mg/m3 at 0.5% and thereafter decreased to 1.53 mg/m3 at 2% of fibre content. In the case of samples treated with waste plastic strips. The MDD progressively increased as the amount of waste plastic strips increased. OMC show an overall trend of increase for BCS treated with sisal fibre, and a general trend of decrease for soil treated with waste plastic strips. The CBR values initially lessened from their natural value of 13.59% to 4.76% at 1% sisal fibre and subsequently increased to 10.57% at 2% sisal fibre. Similar behaviour was observed for soil modified with waste plastic strips. Based on the results, BCS/waste plastic strips improved the soil more than BCS/sisal fibre treated soil and is recommended at optimal 2% waste plastic strips for geotechnical engineering application such as road payment.

Preliminary data on critical element contents in lignite from the Maritsa East basin, Bulgaria

The studied samples include three composite coal, three lithotypes (lyptain, xylain, and fusain), and a black clay parting from the Troyanovo 1 and Troyanovo North mines in the largest Maritsa East lignite basin in Bulgaria. Mineral matter in composite coal samples, lithotypes, and clay is represented by clay minerals (montmorillonite, kaolinite, illite), quartz, pyrite, and gypsum in various quantities. A total of 66 elements were measured in all samples. The measured concentrations were compared to worldwide values of brown coal and upper continental crust and coefficients of enrichment (K1 and K2, respectively) were established. Most of the studied critical elements (REY, platinum-group metals, Li, Si, Mg, Ge, Ga, Nb, Sb, In, Co, Be, W) have low concentrations (K1 and K2 &lt;2). The content of rare earth elements, yttrium, and scandium in the studied composite coal and lithotype samples is lower than concentration in world low-rank coal (65 ppm) and lower than in the studied black clay (145 ppm). The K1 and K2 coefficients of Pd and Pt, Te, Re, and Au are anomalously high. The mode of occurrence of most trace elements is mineral matter (sorbed in clay minerals, trace elements in pyrite, and as discrete phases). Some elements in low-ash samples (lithotypes) demonstrate affinity to organic matter: Te, Re, As, Mo, Ca, P, Au, Ba, Sr, Cd, etc. The lithotypes show enrichment in HREE (Gd–Lu) and Y in the following decreasing order: xylain &gt; fusain ≫ liptain. The anomalously high contents of Te, Re, Pd, Pt, Au, Se, As, Mo, and others require further investigation.

Effects of Unconventional Water Agricultural Utilization on the Heavy Metals Accumulation in Typical Black Clay Soil around the Metallic Ore

Unconventional water is an important water resource for agricultural utilization in the drought and water shortage of Northeast China. Additionally, exploration in making full use of it is an important way to alleviate water shortage in China. This paper analyzed the effects of unconventional water through field trials on the accumulation of heavy metals in both cucumbers and the typical black clay soil (expressed as black soil) around the Anshan metallic ore. By exploring the effects of unconventional water after secondary treatment on the accumulation characteristics of heavy metals in cucumbers and the heavy metal balance in the soil–crop system under different conditions, the study shows that there are no significant differences in the heavy metal content when the quantity of unconventional water for irrigation varies. Unconventional water for short-term irrigation does not cause pollution to either the soil environment or the crops. Nor will it cause the accumulation of heavy metals, and the index for the heavy metal content is far below the critical value of the trade standard and national standard, which indicates that the crops irrigated with unconventional water during their growth turn out to be free of pollutants. Unconventional water brings less heavy metals into the black soil than crops. The input and output quantities have only small effects on the heavy metal balance in the black soil. This paper provides a reference for the safety control and evaluation of unconventional agricultural utilization.

Development of Characteristics and Thermal Properties of Ash Celadon Glazes in Thailand

In this paper, we will study the development and comparison of characteristics and thermal properties of original celadon glazes and celadon glazes developed by adding black rice husk ash, Using Mae Rim black clay in Chiang Mai Province as raw material for the original celadon glaze (CG), including clay in the rice paddies, Kha wood ash and mixed wood ash. The raw materials for the development of celadon glazes formula were 14BR, 15BR, 20BR, 21BR, 27BR and 28BR, respectively. Using a triangular phase diagram system, Mae Taeng clay (MT), Kha wood ash (KWA) and black rice husk ash (BR) were used in the ratios of 40, 50, 60 and 70 wt.%, and using the red clay from Doi Saket, Chiang Mai as a coloring agent. Subsequently, the raw materials are ground and mixed to form a coating. Coated onto Mae Rim black clay test specimens. and fire the test specimen at 1250 °C in a reducing atmosphere. After that, the characteristics of the glazes after firing were tested, including crack, melt, flow, color appearance, and chemical composition. Thermal properties tests include the coefficient of thermal expansion and thermal shock resistance in temperature. The results showed that by comparing the original formula celadon glazes (CG) with the celadon glazes formula developed by adding black rice husk ash. crazing were reduced when adding more black rice husk ash. All formulations were melted at 1250 °C due to their CaO content of 55.0, 47.6, 41.0, 51.0, 47.9, 47.7 and 43.0 % respectively. From the chemical composition analysis with XRF, celadon glazes after firing in all formulas did not see any flow due to the content of SiO2 being 28.0, 28.8, 35.4, 26.7, 28.3, 27.9 and 31.1% respectively. The appearance of glazes after firing was more greenish-yellow when rice husk ash was added when using a color analyzer. Because the amount of Fe2O3 up to 4.6, 9.3, 10.4, 8.2, 9.1, 5.9 and 6.0% respectively from Mae Taeng clay and Doi Saket clay. The chemical composition of celadon glaze consists of CaO as the main component, followed by SiO2 and Fe2O3. The important thing is the chemical composition of the glazes was not found with lead and cadmium. The thermal expansion coefficient of celadon glazes at 25-1250°C decreased when adding more black rice husk ash. Finally, the percentage of strength loss after thermal shock temperature change was CG ˃ 20BR ˃ 21BR ˃ 27BR ˃ 28BR ˃ 14BR ˃ 15BR, respectively, using the Celadon Pottery Community Standards Test. (MorChor. 245/2013).

Formulation and Stability Determination of Anti-Acne Cream Containing Black Cumin Seed Oil and Kaolin Clay

Acne is the most common skin problem that could occur to any individual. Nigella sativa seed oil and kaolin as natural antimicrobial agents have been utilized in anti-acne cream formulated in this study. This study aimed at the development of anti-acne cream with antimicrobial properties using a crude extract of black cumin (Nigella sativa L.). Anti-acne creams had been formulated from cream-based agents with various percentages of crude black cumin seed extract and 1.0% (w/w) of mineral clay (Kaolin). Physical properties and stability of anti-acne cream at various storage conditions, including incubation at and freeze-thaw at 4, 40, and 45 °C for 28 days. The results showed that developed anti-acne cream containing a crude black cumin seed extract in 0.1 and 1.5% (w/w) had good physical stability. Therefore, the suitable formulation was then tested for anti-Propionibacterium acnes (P. acnes) susceptibility by the broth dilution method. From these results, it was found that 1.0 % (w/w) of crude black cumin seed extract had the ability to inhibit P.acnes with MIC (minimal inhibition concentration) of 15.6 mg/mL.

Experimental design for the optimization of dry-pressed ceramic bricks (Dry-Press)

One of the most common products in the construction industry is brick due to its advantages over other building materials such as blocks. In developing countries like Ecuador, brick is handcrafted and is the source of income for thousands of families. These bricks lack a systematized process that optimizes resources to make a brick that meets local regulations. This study evaluates the use of the different raw materials used in production through experimental designs to determine the amount of optimal components locally available (“White Clay,” “Black Clay,” “Water”) and achieve the maximum compressive strength in dry-pressed ceramic bricks. This research also identifies the behavior of the compressive strength based on the compaction pressure in the molding stage, concluding that the model that best fits the behavior is a quadratic model, and from the trace plot, it was observed that compared with “White Clay,” “Black Clay” contributes further to the brick strength. The optimal amount of components to meet the 6 MPa pressure standard required in the brick was 5% water, 85% “Black Clay” and 10% “White Clay.” The pressure value required in the compaction stage was 4.9Mpa (712psi,) and greater strength can be achieved by only adding “Black Clay” and water.

Outstanding Performance of a New Exfoliated Clay Impregnated with Rutile TiO2 Nanoparticles Composite for Dyes Adsorption: Experimental and Theoretical Studies

Pure rutile TiO2 nanoparticles (Rt) were combined with exfoliated black clay (BC) to prepare a new composite for water decontamination, in particular, for the uptake of methylene blue (MB) and methyl orange (MO) dyes. The as-prepared Rt/BC was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and Field emission scanning electron microscopy (FESEM) techniques, and the dyes’ adsorption isotherms at three temperatures (i.e., 25, 40, and 50 °C) were studied. The results indicated that Rt/BC displayed a high removal performance for MO (96.7%) and MB (91.4%) at pH 3.0 and 8.0, respectively. Adsorption data of MB and MO were adjusted by a double layer model at all temperatures. The theoretical parameters of this statistical physics model were interpreted to understand the MO and MB adsorption mechanisms at the molecular level. The removed molecules per active site (n) of Rt/BC ranged from 1.12 to 1.29 for MB and 1.47 to 1.85 for MO, thus representing parallel orientation and multi-interactions mechanisms (i.e., van der Waals forces, hydrogen bonding, and electrostatic interactions were involved). The Rt/BC composite had a density of surface adsorption sites of 100 mg/g. The aggregation of MO molecules was high and increased their adsorption capacities (Qsat = 294–370 mg/g) compared to that of MB (Qsat = 214–249 mg/g). Adsorption energies were 9.70–20.15 kJ/mol, and these values indicated that MO and MB adsorption processes were endothermic and occurred via physical interactions. Overall, the low cost, high regeneration performance, and stability of Rt/BC support its application as a promising adsorbent for organic pollutants from wastewaters.

Evaluation on Stabilization Role of Lime and Cement in Expansive Black Clay–Oyster Shell Ash Composite

Evaluation on Stabilization Role of Lime and Cement in Expansive Black Clay–Oyster Shell Ash Composite

Yield gap analysis in kharif sorghum hybrid CSH-16 across 12 districts of north interior Karnataka, India : Yield gap in kharif sorghum hybrid

In North Interior Karnataka (NIK) sorghum is grown during both kharif and rabi seasons and CSH-16 is a nationally released hybrid for kharif season. The yield gap analysis is very essential to quantify the difference between potential yield (i.e., no moisture stress) and actual yield of a given crop cultivar under rainfed conditions so that agronomic adaptations are devised to fill the gap. This plays very important role under rainfed conditions because the yield is often limited by water stress followed by N stress. For this, calibrated and validated DSSAT-CERES was used to run simulations from 1988 to 2018 (31 years) for the kharif sorghum hybrid CSH-16 under potential and rainfed conditions on two predominant soils (black clay and red loamy) across 12 districts of NIK. The results showed that average grain yield for NIK in rainfed condition was 2734 kg/ha, with 2272 kg/ha on black clay soil and 3195 kg/ha on red loamy soil. When crop was grown under potential conditions the yield level improved, on average, by 13.0 % to 3079 kg/ha, with 2630 kg/ha on black clay soil and 3528 kg/ha on red loamy soil, indicating that there is a scope to improve grain yield by providing irrigation at critical stages. Across 12 districts of NIK under current climate (1988-2018) on black clay soils the highest yield gap (76 %) was simulated for Koppal district and the lowest yield gap (0.8 %) simulated for Bidar district. Similarly, on red loamy soils the highest yield gap (25 %) was simulated for Vijayapura district and the lowest yield gap (0.1 %) simulated for Bidar district indicating higher yield gap on black clay soil than on red loamy soil.

Influence of integrated weed management on growth and yield of Kharif maize (Zea mays L.)

A field experiment entitled, “Integrated weed management in Kharif maize (Zea mays L.)” was conducted during Kharif, 2020 at Post Graduate Research Farm, RCSM College of Agriculture, Kolhapur. The experiment was laid out in Randomized Block Design (RBD) having three replications and twelve treatments. The soil of the experimental plot was medium black clay (vertisol) with 90 cm depth, low in available N (250 kg ha-1), high in available P2O5 (30.60 kg ha-1) and medium in available K2O (290.67 kg ha- 1). The status of organic carbon content (0.34%) was low. The electrical conductivity and pH values were 4.2 dSm-1 and 7.10, respectively.Weed free check and tank mixure application of Tembotrinone 42 SC @ 120gm a.i.ha-1 + Atrazine 50 WP @ 500 gm a.i.ha-1 + surfactant @ 2ml/l of water EPoE At 20-25 DAS + fb hand weeding at 40 DAS were on par with each other and recorded significantly the higher growth and yield contributing characters viz., plant height (cm), number of functional leaves plant-1, leaf area plant-1(dm2), dry matter plant-1(g), length of cob (cm), diameter of cob(cm), number of grains, weight of grains cob-1and test weight resulting into significant increase in grain and straw yields of maize as compared to remaining weed management treatments. Tank mixure application of Tembotrinone 42 SC @ 120gm a.i.ha-1 + Atrazine 50 WP @ 500 gm a.i.ha-1 + surfactant @ 2ml/l of water EPoE At 20-25 DAS + fb hand weeding at 40 DAS recorded minimum dry weight of weed, highest weed control efficiency (86.94 %) and lowest weed index (1.79%).Significantly lowest values for growth, yield and yield attributes as well as weed control efficiency was observed in weedy check treatment.

Reconstruction of Paleoecology of Early Miocene Subsurface Deposits from Microflora in the Eboïnda Area (South-Eastern Côte d'Ivoire,West Africa)

The early Miocene palynoflora was recovered from well P1 located in the Aboisso area, about 175 km around of Abidjan (south-eastern Côte d'Ivoire, West Africa). Pteridophyta spores, angiosperm and gymnosperm pollen grains have been identified. The main objective of this work is to inventory all the palynomorphs encountered, to propose a local palynostratigraphy and to reconstitute the paleobotany of our study area during the Tertiary formations north of the lagoon fault. The samples were processed according to the classical procedure of extraction and concentration of palynomorphs. The lithology contains brown to black clays, coarse to fine sands, and reddish to motley clays. This study showed that the dominance of freshwater ferns such as Verrucatosporites usmensis, Laevigatosporites ovatus, Polypodiaceiosporites simplex, Cingulatisporites pseudocicatricosus and leiotriletes adriensis which evokes a swampy environment. Also the development of Bombacaceae (Bombacacidites annae), and the abundance of Pteridophyte spores of the Polypodiaceae family (Verrucatosporites usmensis, Laevigatosporites ovatus, and Polypodiaceiosporites simplex) indicate the climate was tropical with alternating dry and wet periods. Early Miocene sediments are placed in a continental type environment.