Cation Exchange Capacity Values Research Articles

New hybrid nature-based algorithm to integration support vector machine for prediction of soil cation exchange capacity

Soil cation exchange capacity (CEC) strongly influences the chemical, physical, and biological properties of soil. As the direct measurement of the CEC is difficult, costly, and time-consuming, the indirect estimation of CEC from chemical and physical parameters has been considered as an alternative method by researchers. Accordingly, in this study, a new hybrid model using a support vector machine (SVM), coupling with particle swarm optimization (PSO), and integrated invasive weed optimization (IWO) algorithm is developed for estimating the soil CEC. The physical and chemical data (i.e., clay, organic matter (OM), and pH) from two field sites of Taybad and Semnan in Iran were used for validating the new proposed approach. The ability of the proposed model (SVM-PSOIWO) was compared with the individual model (SVM) and the hybrid model (SVM-PSO). The results of the SVM-PSOIWO model were also compared with those of existing studies. Different performance evaluation criteria such as RMSE, R2, MAE, RRMSE, and MAPE, Box plots, and scatter diagrams were used to test the ability of the proposed models for estimation of the CEC values. The results showed that the SVM-PSOIWO model with the RMSE (R2) of 0.229 Cmol + kg−1 (0.924) was better than those of the SVM and SVM-PSO models with the RMSE (R2) of 0.335 Cmol + kg−1 (0.843) and 0.279 Cmol + kg−1 (0.888), respectively. Furthermore, the ability of the SVM-PSOIWO model compared with existing studies, which used the genetic expression programming, artificial neural network, and multivariate adaptive regression splines models. The results indicated that the SVM-PSOIWO model estimates the CEC more accurately than existing studies.

Constitutive model of structural alteration and swelling behavior for Old Alluvium

We describe a constitutive model for the compression and swelling behavior of Old Alluvium, a material with a complex microstructure characterized by Fe-oxides cementation and silt-sized aggregates of swelling clay minerals. Compression loading of this material breaks down the aggregate structure, altering the mineralogy, particle fracture properties, and physicochemical properties. We use cation exchange capacity as a measurable proxy to represent the microstructural evolution that can be linked to changes in compressibility with consolidation stress. At load reversal, the value of cation exchange capacity affects the microscale swelling pressures associated with osmotic repulsion between platelets of expansive nontronite. The micro- and macro-scale stiffnesses are linked through a parameter that relates the disjoining pressure to the macroscopic swelling pressure, and an interaction function. By relating macroscopic strains to microscale osmotic repulsion between expansive clay platelets, the proposed model builds directly on the physicochemical characteristics of the material and achieves a more consistent physical basis for describing the unloading response than prior formulations. We illustrate how the model can provide a framework for interpreting how engineering properties vary vertically with the state of weathering in the Old Alluvium soil profile. This approach should find broader application for other piedmont, transported, residual soils.

Inhibitory and synergistic effects on thermal behaviour and char characteristics during the co-pyrolysis of biomass and single-use plastics

The co-pyrolytic behaviour of single-use plastics (Polystyrene, Low-density polyethylene) and Eucalyptus biomass was investigated at variable temperatures (300, 400, 500, and 600 °C) and the effects of their interactions on the characteristics of solid chars were also studied. The variation in thermal profiles of ‘Δ Mass loss%’ showed the inhibitory and synergistic effects of plastics on the biomass degradation, resulting in higher and lower yields of char composite, respectively. The blend containing polystyrene exhibited the highest synergistic (Δ M ≈ 15.1) and inhibitory (Δ M ≈ - 4) effects. The thermal kinetics of blends also indicated the presence of both the effects through relatively higher and lower apparent activation energies compared to the calculated, before and during the degradation of plastics. Despite low fixed carbon contents and high volatile matter, polymer-coated char composites had higher fuel value indices (36–136%), energy yields (1–26%) and calorific values (15–21%), relative to biochar. After the complete degradation of plastics, char composites exhibited higher values of electrical conductivity (2–40%), surface area (15–64%), and cation exchange capacity (5–19%). These properties advocate the flexibility of char composites' applicability as solid fuel or soil amender depending on the optimized conditions of co-pyrolysis.

Interactions between Cationic Dye Toluidine Blue and Fibrous Clay Minerals

Interactions between cationic dyes and negatively charged mineral surfaces have long attracted great attention from clay mineralogists, environmental scientists, and chemical engineers. In this study, the interactions between a cationic dye toluidine blue (TB) and palygorskite and sepiolite were investigated under different experimental conditions. The results showed that in addition to cation exchange, the specific surface area (SSA) of the minerals, particularly the formation of dimer molecules on the surface of both minerals, also accounted for the much higher TB uptake in comparison to their cation exchange capacities (CEC). The TB molecules were sorbed to the external surfaces, as no d-spacing expansion was observed in X-ray diffraction analyses. FTIR analyses showed strong interactions between the C=N or N-(CH3)2 group and the mineral surfaces, suggesting net electrostatic interactions if either of these functional groups bears a positive charge. Results from molecular dynamic simulations suggested dense monolayer TB formation on palygorskite because of its limited SSA and large CEC values. In comparison, a loosely dimeric formation was revealed on sepiolite for its large SSA and limited CEC values. Therefore, palygorskite is a better carrier for the sorption of cationic dyes, as evidenced by Maya blue paintings.

Methylene Blue Spot Test for Cation Exchange Capacity (CEC) Estimation in Acid Soils of India

In order to establish a simple, rapid and cost effective method of estimating cation exchange capacity (CEC) of acidic soils, we tested the utility of methylene blue spot test (MBST) vis-à-vis commonly used neutral 1N ammonium acetate method (NAAM) in twenty acidic soils. The soils collected from ten different states of India varied widely in pH, organic carbon content and texture. Averaged across the soils, MBST-CEC was 37% lower than the NAAM-CEC, due possibly to the differences in pH at which the two methods operate. The CEC values estimated by MBST correlated strongly (R=0.89) with those obtained by NAAM, implying that MBST can be used satisfactorily to measure CEC of acidic soils. An equation for inter-conversion of CEC values obtained by the two methods was also worked out. Since NAAM is a time taking and tedious procedure, we recommend MBST method for routine estimation of CEC in acidic soils of India. The method is easily applicable with simple test equipments including filter papers, a glass rod or dropper and methylene blue dye. More than 60 samples a day can easily be analyzed for CEC using MBST method. Being a simple, rapid and cost effective method, the MBST can be included in rapid soil testing kits. Given the importance of CEC in soil fertility and plant nutrition, MBST-CEC may also be included in the soil health cards distributed to the farmers.

Synthesis of proton-conducting membranes based on sulfonated polystyrene and bacterial cellulose

Synthesis of composite material based on sulfonated polystyrene and bacterial cellulose as a proton membrane has been carried out. In this study, the membrane was made with the variations mass ratio of sulfonated polystyrene : bacterial cellulose 1,5: 3,5, 2,5: 2,5, 3,5: 1,5. The previous step was sulfonation of polystyrene, in which the polystyrene used is styrofoam from electronic goods packaging waste. Polystyrene in this case styrofoam is sulfonated using the sulfonating agent trimethylsilyl chlorosulfonate. The membranes have characterized by analyzing of functional groups, proton conductivity, cation exchange capacity, and degree of swelling. The FTIR spectrum showed that the sulfonated polystyrene-bacterial cellulose composite material was successfully synthesized which was shown at the peak at wave number 1124.767 cm−1 which was a SO3 stretching vibration. The peak at wave number 962-1150 cm−1 was assigned the stretching of CO vibrations for C-OC and C-OH which indicates cellulose glycosidic bonds. The highest Cation Exchange Capacity (CEC) value and proton conductivity were in the composite membrane: bacterial cellulose mass ratio 3,5: 1,5, the CEC value 2.25 meq/g and the proton conductivity value 1.176 x 10−6 S/cm2. This result shows that the sulfonated polystyrene-cellulose bacterial composite membrane has the ability to deliver protons so that it has the potential to be developed as a fuel cell membrane.

Metals removal from surface and wastewaters using an eco-friendly and sustainable material

In this study, the potential metal adsorption properties of a Romanian natural and activated (by chemical, thermal and thermo-chemical treatments) zeolite was tested for further use in water treatment. The structural changes of zeolite after activation were studied by X-ray diffraction (XRD), Fourier-transform infrared spectrometry (FT-IR) and cation exchange capacity (CEC) analysis. Adsorption experiments were carried out for 72 h at room temperature, using a zeolite/liquid ratio of 1 g/50 mL using highly contaminated surface and wastewaters. The metal concentrations (Mn, Fe, Ni, Cu) were determinate before and after the adsorption experiments using inductively coupled plasma mass spectrometry (ICP-MS). Although, the chemical and thermo-chemical activation methods had a positive effect on the CEC values, the FT-IR and XRD analyses did not indicated any notable changes in the zeolite structure. The obtained results showed that the highest metal removal efficiency was reached for the thermally activated zeolite. After 72h, the metal removal efficiency ranged between 12.8 and 100% in the case of surface waters and between 1.55 and 59.2% in the case of wastewaters.

Mineralogical and physico-chemical characterization of gypsiferous semi-arid soils in the north of Urmia, Iran

Gypsiferous soils contain sufficient gypsum to influence soil physico-chemical, mineralogical, mechanical properties and geotechnical conditions and as a consequence, affect plant growth and crop production. So physico-chemical and mineralogical properties of 6 soil profiles located on the gypsiferous parent material with semi-arid climate in north of Urmia, West Azerbaijan province, Iran, were investigated. Based on standard methods, morphological, physico-chemical and mineralogical properties of these soils were determined. Soils with higher gypsum content had lighter color, lighter texture, lower values of organic carbon and cation exchange capacity and higher values of electrical conductivity. These parameters were reversely changed with decreasing gypsum content of soils. Semi-quantitative analysis of clay minerals indicated the presence of smectite, illite, chlorite, kaolinite and palygorskite were as major clay minerals with decreasing order from smectite to palygorskite. The origin of illite, chlorite and kaolinite were related to the inheritance from parent material. Smectite group of clay minerals has been resulted from three origins of inheritance from parent material, transformation of illite and palygorskite and neoformation, but the transformation and neoformation are the main pathways for its formation. Palygorskite has pedogenic origin and has been formed via neoformation. The comparison of clay mineralogy of soils with different gypsum values revealed the presence of higher smectites in soils with higher gypsum. Palygorskite was identified just in soils with higher gypsum. In soils with lower values of gypsum, illite and chlorite were the predominant clay minerals and palygorskite did not identified.

The Effects of Pyrolysis Temperature on Chemical Properties of Empty Fruit Bunch and Palm Kernel Shell Biochars

Biochar is a valuable by-product which has a potential as a new soil amendment in improving soil fertility. However, the properties of biochar highly depend on the types of feedstock used and the pyrolysis condition. Therefore, this study was conducted to evaluate the effects of pyrolysis temperature on chemical properties of biochar derived from oil palm. Two types of biochars were produced from empty fruit bunch (EFB) and palm kernel shell (PKS) by slow pyrolysis process applied at different levels of pyrolysis temperature (350, 500 and 750°C). The chemical properties of biochars such as pH, electricity conductivity (EC), total nutrients and cation exchange capacity (CEC) were determined. The adsorption capacities of cadmium on biochars also were investigated. The results showed that pH value, EC and total macronutrients for both EFB and PKS biochars increased with the increased of temperature. In contrast, CEC value decreased when pyrolysis temperature is increased. Biochar derived from EFB produced at 750°C showed the highest adsorption capacity of cadmium.

Changes in the chemical properties of coir dust with increasing aging time and development of a method for determining moderate aging degree

The objective of this study was to create a method to evaluate the aging of coir dust. A rainproof plastic house was used to monitor the fresh coir dust for 24 weeks, and the samples were collected every 2 weeks during aging. The aging effects on coir dust were investigated with the changes in mineral nutrient contents and plug seedling growth in four different vegetables. Experiments were conducted to determine the appropriate degree of aging by analyzing the changes of total phenol and tannin contents, color, and near-infrared spectral characteristics as influenced by the aging duration of coir dust. The pH, electrical conductivity (EC), and cation exchange capacity (CEC) values of the non-aged coir dust were 5.04, 9.19 dS m−1, and 75.2 cmol+ kg−1, respectively. The concentrations of Cl and K in the non-aged coir dust were 4061.8 and 3487.4 mg kg−1, respectively. The contents of total phenol and tannin in the non-aged coir dust were 168.8 and 38.8 mg kg−1, respectively. The pH rose continuously to 5.94 at 24 weeks, and the EC decreased to 1.8 dS m−1 after 4 weeks of aging and then remained at a similar level. The concentrations of elements decreased drastically except for NH4+ and NO3− until 4 weeks of aging, and later they remained at a similar level. The total phenol content decreased greatly at 2 weeks of aging, and the tannin content decreased continuously from 38.8 mg kg−1 in week 0 to 0.15 mg kg−1 at 24 weeks of aging. The color indicators b* and C* decreased until 12 weeks of aging, and after that, they remained at a similar level. The optimum aging of coir dust was judged based on b* and C* values. The spectral analysis showed that the coir dust aged over 18 weeks could be distinguished from the earlier stage of aging with 91% accuracy. When the coir dust with varied aging durations was used as a root substrate, the fresh weights of radish, Korean cabbage, tomato, and red pepper increased quadratically as the aging period of the coir dust became longer (R2 = 0.7824, 0.7529, 0.4718, and 0.5458 in radish, Chinese cabbage, tomato, and red pepper, respectively; p ≤ 0.001).

Luminescence of a laser dye in organically-modified layered silicate pigments

The main focus of the present work was the development of pigments based on layered nanomaterials exhibiting luminescent properties. Two layered silicates, montmorillonite (Mt) and saponite (Sap), differing in their cation exchange capacity (CEC), were modified with cationic organic surfactants (tetraoctylammonium and tetraoctylphosphonium) in various amounts relative to the CEC (25–100%) and with a laser dye, rhodamine 6G (R6G), with dye/silicate ratios of 0.001–0.08 mmol g−1. The photoluminescence and its dependence on the surfactant amount, dye concentration, and the layered silicate type were evaluated. Modification by the surfactants played a key role and caused an increase in fluorescence, particularly for Mt, whose hybrids were non-active without the modification. The intensity increased significantly even for samples modified with amounts of surfactants equal to 25% of the CEC values. Dye concentrations above 0.02 mmol g−1 caused a diminishing of the fluorescence intensities due to the formation of non-luminescent molecular aggregates of the dye. Advanced chemometric and statistical analysis was applied for better differentiation of the components in fluorescence spectra. By selecting suitable organic cation and dye components, it was possible to prepare pigments exhibiting high fluorescence and at (for R6G) unusually long wavelengths, approaching the near-infrared region (650–700 nm).

Enhancement of soil physico-chemical properties post compost application: Optimization using Response Surface Methodology comprehending Central Composite Design

The application of compost has been recognized as one of the most promising approaches for preserving soil quality and crop production. The present study exhaustively investigates the impact of Water Hyacinth Compost (WHC), Hydrilla verticillata Compost (HVC) and Vegetable Waste Compost (VWC) on soil nutrient quality and engineering properties [Bulk Density (BD), water retention and specific gravity]. For the study, six different proportions constituting 5, 10, 15, 25, 35 and 45% of the composts by weight of the soil were taken. The soil compost mixtures were evaluated at different periods (0, 15, 30, 45, 60 and 120 days) for various nutrients [Na, Mg, P, K, Ca, Total Organic Carbon (TOC), Total Kjeldahl Nitrogen (TKN)], BD, water retention capacity, change in specific gravity and Cation Exchange Capacity (CEC) values. It was observed that when the percentage of compost was increased to 15–45%, it resulted in enhanced nutrient value of the soil. Also, for WHC, HVC and VWC 60 days was sufficient to improve the soil quality to its maximum extend. Based on the optimized physico-chemical properties generated from the Response Surface Methodology (RSM) model, it was found that compared to WHC and HVC, the VWC performed better results viz., generating low BD (0.87 g/cm3), high water retention capacity (45.63%) and degree of saturation (77.49%) of the soil. While WHC, HVC and VWC can be used to improve soil nutrient content and overall physico-chemical parameters in long terms, VWC could be more efficient and beneficial to degraded soil for restoring soil health.

Establishment and verification of prediction models for evaluating the physical and chemical properties of soilless substrates

In soilless culture, a suitable mixed substrate that provides a balanced and stable rhizosphere environment is vital for promoting plant growth. The present study was undertaken to establish seven prediction models of physical and chemical properties, including bulk density (DB), total porosity (TP), water-holding porosity (WHP), air porosity (AP), WHP/AP, electrical conductivity (EC) and cation exchange capacity (CEC) of mixed substrate based on regression equations of measured values from 76 substrate combinations. These seven models were verified using the measured values of 12 mixed substrates, and the average relative prediction errors (REs) were all less than 10%. A comprehensive property prediction model was established by weighted summation of the seven models of physical and chemical properties. According to the set values of DB, TP, WHP, AP, WHP/AP, EC and CEC, the comprehensive property model predicted the six mixture proportions of mixed-substrate, as verified using the measured values. This study is the first to establish prediction models for the physical and chemical properties of mixed substrates. The comprehensive property model could be used to evaluate the physical and chemical properties of commercial mixed substrates, and to provide the optimal mixture substrate formulations according to the setting property value of production requirement. Keywords: prediction model, mixed substrate, physical and chemical properties, multiple regressions, genetic algorithm DOI: 10.25165/j.ijabe.20211402.5815 Citation: Gong B B, Wang N, Zhang T J, Li S, Wu X L, Tian J, et al. Establishment and verification of prediction models for evaluating the physical and chemical properties of soilless substrates. Int J Agric & Biol Eng, 2021; 14(2): 9–18.

Impact of weather changes on the potato cultivation quality with the LEISA system

The aspect of potato cultivation well known to most farmers is closely related to the climatology of the cultivated site. Therefore, this study aims to obtain the basic information on climatic change in potato cultivation quality using the LEISA system or in potato cultivation, compost is used as fertilizer at a dose of 10-30 tonnes/ha. The experiment was designed based on four treatments namely, (1) cultivation in normal weather conditions from April - June 2019, (2) in foggy air conditions from July to September 2019, (3) in extremely hot conditions from October to December 2019, and (4) in extremely rainy conditions from January to March 2020. The parameters observed were (1) microclimates around the plants, (2) the condition of the growing media depth 0-30 cm, (3) plant growth, and (4) productivity. The changes from normal to foggy, extremely rainy, and hot weather had impacts on soil temperature by 22.1±5.2%, 8.6±2.2%, and 10.3±5.9% respectively. In extremely hot and rainy weather, the cation exchange capacity (CEC) value was low by 22.1±0.16 and 23.8±0.21 meq/100g of dry soil. The extremely hot, rainy, and foggy weather reduced the productivity of potato plants by 32.13–60.2%, 19.5– 43.0%, and 16.7–18.0% respectively. In addition, they also reduced the quality of potato tubers by 19.9–94.7%, 26.0–62.9%, and 8.8–15.9% respectively.

Effect of amendment sources under subsurface drainage system on physical and chemical properties of sodic soil

The present investigation was undertaken to study the effect of amendment sources under subsurface drainage system on physical and chemical properties of sodic soil classified as a fine montmorillonite hyperthermic family of Sodic Calciustert. The field experiment was conducted at Post Graduate Institute, Research Farm, Department of Soil Science and Agricultural Chemistry, MPKV, Rahuri, during Kharif 2019. Experimental soil showed strongly alkaline reaction, normal electrical conductivity, medium organic carbon content and moderately calcareous. The experiment was laid out in a randomized block design with three replication and twelve treatments. The treatment comprised of T1: Absolute control, T2: Gypsum as per 100% GR, T3: Elemental sulphur as per 1/5th of GR, T4: Zeolite @ 600 kg ha-1, T5: Gypsum as per 100% GR + zeolite @ 600 kg ha-1, T6: Gypsum as per 50% GR + zeolite @ 600 kg ha-1, T7: Gypsum as per 100% GR + zeolite @ 300 kg ha-1, T8: Gypsum as per 50% GR + zeolite @ 300 kg ha-1, T9: Elemental sulphur as per 1/5th of GR + zeolite @ 600 kg ha-1, T10: Elemental sulphur as per 50% of 1/5th GR + zeolite @ 600 kg ha-1, T11: Elemental sulphur as per 1/5th of GR + zeolite @ 300 kg ha-1 and T12: Elemental sulphur as per 50% of 1/5th GR + zeolite @ 300 kg ha-1. The results of investigation revealed that, the amendments applications in sodic soil under SSD system was influenced the soil physical and chemical characteristics. Significant results were found in reclamation of sodic soil. The physical properties of soil i.e. hydraulic conductivity and bulk density of sodic soil in SSD field was significantly improved by treatment Gypsum as per 100% GR + zeolite @ 600 kg ha-1 at harvest of crop.ESP and exchangeable cations i.e. Ca2+, Na+, Mg+ and K+ content of sodic soils in SSD field after harvest of crop was significantly influenced by treatment Gypsum as per 100% GR + zeolite @ 600 kg ha-1 except exchangeable Mg2+ which shows nonsignificant effect. Soil organic carbon, calcium carbonate and cation exchange capacity of sodic soils in SSD field are influenced by the inorganic amendments after harvest of crop. The organic carbon content of sodic soils in SSD field was significantly higher in treatment Gypsum as per 100% GR + zeolite @ 600 kg ha-1, applied Elemental sulphur as per 1/5th of GR + zeolite @ 600 kg ha-1 was found significantly lower values of CaCO3 and cation exchange capacity was significantly increased by the Gypsum as per 100% GR + zeolite @ 600 kg ha-1. The SAR in which cations and anions in saturation paste extract of sodic soil in SSD system was significantly influenced by treatment Gypsum as per 100% GR + zeolite @ 600 kg ha-1 after harvest of crop. Whereas, sulphate content was non-significant and carbonates was in trace amount.

Evaluation of the Free Swell and Physio-chemical Properties of Black Cotton Soil Treated with Bacillus Coagulans

The effect of Bacillus coagulans (B. coagulans) on the free swell and physio-chemical properties of black cotton soil (or expansive tropical black clay) was investigated using the Microbial Induced Calcite Precipitation (MICP) technique. Black cotton soil was treated with different mix ratios of B. coagulans suspension density (B) and cementation reagent (C) for the volume obtained as product of the liquid limit and a specific weight of soil sample. The mix ratios considered were 25B-75C, 50B-50C and 75B-25C for the treated specimens, while the control specimen was mixed with 100C only. The results obtained show that for treatment of soil with 25B-75C mix ratio, free swell value decreased with increased B. coagulans suspension density from 70.0 % and 50.0 % for the natural and control specimens, respectively, to minimum value of 40.0 %, at B. coagulans suspension density of 2.4 × 109 cells/ml. The cation exchange capacity (CEC) value for the natural and control specimens were 49.7 and 29.6 Cmol/Kg, respectively, while for the treated specimens the values generally decreased a minimum value of 29.0 Cmol/Kg at B. coagulans suspension density of 2.4 × 109 cells/ml. The pH test results initially decreased from 7.4 for the control specimen to a minimum at of 7.37 at B. coagulans treatment suspension density of 1.5 × 108 cells/ml and thereafter gradually increased to 7.51 at peak B. coagulans suspension density of 2.4 × 109 cells/ml. Tests results indicate that treatment of black cotton soil with 25B-75C mix ratio at 2.4 × 109 cells/ml B. coagulans suspension density significantly reduced the free swell value and makes it useable for engineering application.

Uptake capacity of zeolitic tuff from Gunungkidul, Indonesia for environmental and agriculture application

Zeolitic tuff samples from Gunungkidul Yogyakarta, Indonesia was investigated for mineralogical and chemical composition and its uptake capacity. Five zeolitic tuff samples were obtained from the field and measured for the mineralogical, chemical composition, and uptake capacity by XRD analysis, ICP AES, and BaCl2 method, respectively. The result of mineralogical composition showed that the mordenite type-zeolite was found as significant zeolite mineral, with percentages varying from 24.1% to 38.1% and with an average amount of 34,3%. Chemical analysis revealed that the mordenite contents influenced amounts of SiO2 ranging between 60.06% to 66.06% and Al2O3 from 12.12% to 13.57%, and this Si/Al ratio obtained. The measured uptake capacity or cation exchange capacity (CEC) value varies from 67 meq/100 g to 98 meq/100 g with an average value of 82,4 meq/100 g. The vary of these values most probably was influenced by the differences in the percentage of zeolite minerals and other mineral impurities. Mordenite type of zeolite is thought the most affected of the uptake capacity, while clay minerals contribute to a relatively small influence. The uptake capacity of the five zeolitic tuff studied showed positive correlations with the content of mordenite-type zeolite as well as with the total content of microporous minerals and Si/Al ratio. These materials could be an excellent material candidate in a wide range and scale of agricultural, and environmental applications.

Mapping of cropland suitability at marginal area Situbondo district

Marginal land development in Situbondo Regency has not yet received special attention from farmer as the farmer-enterpreneur, so that the efforts made by stakeholders have not yet gotten maximum results. Therefore, increasing awareness and understanding of the development and use of marginal area is needed. The objectives of this study are: 1) knowing the land characteristics of crops commodities at marginal land and (2) mapping the suitability of cropland at marginal land. The locations of the study are Jatibanteng and Sumbermalang Subdistricts with the consideration that the subdistrict is the area where the majority of rice fields are dry and marginal area in Situbondo Regency. The research method uses an analytical approach. The data collection method is using secondary data, which is available statistical data that has been published by BPS and primer data. The data analysis method uses SRTM (Shuttle Radar Topography Mission) and soil chemical analysis. The results showed that of (1) the land characteristics can be seen from soil chemical analysis including: a) Phosfor content of land ranged from 28,06-84,28 me/100g which was dominated by high status; b) Potassium value of land ranged from 16.95-59.96 me/100g which was dominated by moderate status; c) Organic matter content of land ranged from 1.75-3.39% which was dominated by medium status; d) Cation Exchange Capacity (CEC) value of land ranged from 14.76 - 37.03 me/100g which was dominated by the high status; and e) Base Saturation in Jatibanteng Subdistrict was classified as low to moderate, ranged from 30.39% - 50.10% and Sumbermalang subdistrict ranged from 20.15% - 48.62%. Provision of organic material is a way that can be applied to increase the value of BS, because organic matter affects soil properties such as its physics and chemistry. (2) Meanwhile the the second objective was found that: a) around 35% of Jatibanteng Subdistrict was in the S1 (Highly Suitable) category; on the other hand, Sumbermalang Subdistricts was in the S2 (Moderately Suitable) and S3 (Marginal Suitable) categories for the rice field suitability, b) class suitability of corn in the study area was included in the more dominant of S2 (Moderately Suitable) category reaching almost 85% of the land areas, and c) cassava plants had an S1 (Highly Suitable) suitability class dominated by Jatibanteng Subdistrict which was almost 50% of its areas in Sumbermalang Subdistrict with the suitability of S2 (Moderately Suitable) and S1 (Highly Suitable).

Sustainable ammonium recovery from wastewater: Improved synthesis and performance of zeolite N made from kaolin

Abstract Although zeolite N ( K 12 A l 10 S i 10 O 40 C l 2 . 8 H 2 O ) is used commercially for the removal and recovery of ammoniacal nitrogen from wastewater, it has received limited attention in academic literature. The hypothesis was that if an improved understanding of zeolite N synthesis and resultant physical parameters and performance can be acquired, then the application of this material may be accelerated. This study successfully addressed existing research challenges including: maximizing the cation exchange capacity (CEC); selection of preferred synthesis conditions; control of the size, shape, and dispersion of zeolite N crystals; and improvement of ion exchange properties. Zeolite N was hydrothermally synthesised from kaolin clay added to solutions of potassium hydroxide and potassium chloride in a “one pot” process. CEC values increased to 563 meq/100 g (c.f. 528 meq/100 g in previous literature). Reaction between 120 and 140 °C for 2–4 h under static conditions was preferred as higher temperatures (180 °C) produced kalsilite. The KOH molarity (1.2–4.3 M) controlled the average zeolite crystal size, dispersion, and crystal shape; with highest molarity values optimal. Whereas, added KCl acted as a template which promoted zeolite N formation. Removal of KCl resulted in creation of zeolite F ( K 13 ( O H ) 3 A l 10 S i 10 O 40 . 13 H 2 O ) which also belonged to the EDI structural type. Ammonium ion exchange from aqueous solution was improved when diffusion restrictions were eased; as evidenced by using smaller zeolite crystals which were highly dispersed and not agglomerated. Not only was a greater cation capacity recorded but also the time to reach equilibrium was decreased.

A novel technique for Cd removal from soil based on alginate-derived floatable spheres

This paper proposes a fast, facile and eco-friendly strategy for removing Cd from soil. By combining two types of floatable alginate-derived multifunctional spheres: magnetic hollow carbon composite (MHCC) and calcium alginate aerogel (CAA) spheres, the fixed state Cd in soil is activated and removed sequentially. MHCC spheres activate and desorb the solid phase anchored Cd into mobile Cd2+ ions, and CAA spheres effectively absorb the free Cd2+ ions from the liquid phase via the massive absorption sites of carboxy and hydroxy groups. The remediation results of 5-round successive MHCC-CAA treatments (1.5 g MHCC-0.45 g CAA in 60 g soil) show that 44.02% of Cd is removed from the soil. MHCC spheres demonstrate excellent recyclability of 88.87 and 94.45% in flooding and non-flooding soil, respectively. The texture, cation exchange capacity (CEC) and pH value of the remediated soil suggest that the MHCC-CAA system has little interference on the soil properties. No remarkable hindrance of microbial growth by MHCC or CAA spheres is observed in the eco-toxicological test, indicating the ecological friendliness of MHCC-CAA remediation system.