Reduced Bulk Density Research Articles

Performance of lightweight foamed concrete partially replacing cement with industrial and agricultural wastes: Microstructure characteristics, thermal conductivity, and hardened properties

The production of eco-friendly concrete has been made possible by reusing agricultural and industrial wastes. This paper presents an experimental investigation of the characteristics of lightweight foamed concrete (LWF) produced from a protein-based foaming agent and including granulated blast furnace slag (GGBS), fly ash (FA), rice husk ash (RHA) and palm oil fuel ash (POFA) at various substitution levels (0, 10 %, 20 %, 30 %, 40 %, 50 %, and 60 %) with cement. By executing a slump test, the fresh characteristics of mixes were assessed. In addition, a total of 25 different LWF mixtures were produced and tested for their porosity, bulk density, compressive strength, bending strength, splitting tensile strength, water absorption, ultrasonic pulse velocity (UPV), and thermal conductivity. To elucidate the causes for the experimental findings acquired, microstructural analysis was also performed. The findings indicate that the GGBS, FA, RHA, and POFA ratios of the LWFs increased due to a reduction in slump, porosity, water absorption, bulk density, and thermal conductivity up to 40 % GGBS, 30 % FA, 20 % RHA, and 30 % POFA. However, the compressive strength, bending strength, splitting tensile strength, UPV were raised up to 40 % GGBS, 30 % FA, 20 % RHA and 30 % POFA as substitution for cement. LWF containing 40 % GBS as a cement substitution also demonstrate larger compressive strength, bending strength, splitting tensile strength, and ultrasonic pulse velocity in comparison with the control, 30 % FA, 20 % RHA, and 30 % POFA LWF. The findings are promising and reveal a major opportunity for developing eco-friendly LWF by partially substituting cement with GGBS and FA industrial by-product material, RHA and POFA agricultural waste materials as well.

Design and fabrication of the alumina nanofibers decorated with isolated ZSM-5 using electrospinning method: A novel catalyst for methanol conversion to light olefins

ZSM-5 nanoparticles are widely used as the catalyst in the methanol conversion to olefins (MTO) process due to their high surface area and short diffusion path length. However, agglomerate formation is a challenge for this catalyst. To address this issue, in this study, electrospinning was used for the first time to synthesize fibrous catalysts comprised of ZSM-5 nanoparticles embedded in the alumina nanofibers. The catalysts were characterized using XRD, FTIR, SEM, TEM, EDX-map, BET, and NH3-TPD analyses. In the synthesized samples, ZSM-5 nanoparticles with an average particle size of 683 nm are uniformly and homogeneously dispersed over alumina nanofibers with a 300 nm diameter. These composites form core-shell structures and have a reactor porosity of 0.85, which is higher than that of parent ZSM-5. In the MTO process, electrospun catalysts demonstrate superior catalytic activity and a longer lifespan than powder catalysts. 80 wt% ZSM-5- 20 wt% Al2O3 with 47.76 % light olefin selectivity and complete methanol conversion after 321min on stream performed better than 50 wt% ZSM-5-50 wt% Al2O3. Moreover, a lower coke formation of about 3.28 % was achieved for the 80 wt% ZSM-5- 20 wt% Al2O3 sample. The reduced bulk density of the electrospun samples increases the probability of reactant and catalyst contact. Additionally, electrospinning is an effective method for reducing particle aggregation and improving catalytic process efficiency.

Quantifying the Influence of Enriched Urban Compost and Wastes on Soil Physico-chemical and Biological Parameters of Bettahalli Village, Bangalore North Taluk: A Quantitative Analysis

Enriched urban compost enhances soil for sustainable agriculture, improving structure, water dynamics, nutrient release, microbial life, and contributing to climate change mitigation. The present study was carried out in 2022 late winter to assess the impact of enriched urban compost and wastes on soil properties. Collected Soil samples were analyzed for physical, chemical, and biological properties pre and post-maize harvest. Enriched urban compost treatments showed a slight reduction in bulk density. Increased Moisture holding capacity, pH, electrical conductivity, organic carbon, and magnesium remained mostly unchanged.
 Nitrogen, phosphorus, and potassium increased significantly with enriched compost, promoting sustained nutrient release. Available sulfur rose with compost addition. DTPA-extractable Cu, Zn, Fe, Mn, and B were significantly higher with enriched compost. Chromium, nickel, lead, and cadmium remained below critical limits. Dehydrogenase and urease activities were significantly higher with enriched compost, indicating enhanced microbial action. Acid phosphatase activity increased, likely due to elevated phosphorus levels in organics, supporting P solubilizers.
 Enriched urban compost enhances soil properties, promoting agricultural sustainability through climate change mitigation, improved structure, and enhanced nutrient release. Advisably, incorporating enriched urban compost into agricultural practices optimizes soil health, fosters sustainable nutrient management, and supports microbial activities, thereby enhancing agricultural productivity.

Effect of Soil Bulk Density on Water Infiltration in Layered Soil

Abstract: The optimal design of various irrigation systems requires knowledge and a deep understanding of various soil properties. Water infiltration in the soil is among the most prominent of these characteristics. Ten laboratory experiments were conducted to study the effect of the bulk density of stratified soils (two-layered soils), Where sandy loam soil, and clay soil were used. Three bulk density values were adopted for each soil, and experiments were conducted in different sequences. New empirical relationships were derived to calculate the cumulative infiltration depth and the depth of the wetting front in terms of time and the basic infiltration rate of the soil. The results revealed a high agreement between the values measured in the laboratory and those estimated from the proposed empirical equations for infiltration and wetting front depths with a coefficient of determination of 0.96 and 0.98, respectively. The results showed that the infiltration and wetting front depths increased with the cumulative infiltration time and the soil bulk density reduction, regardless of the soil location in the upper or lower layer within the stratified soil. It was also found that the infiltration rate was affected by the density of the upper stratum more than its influence by the change in the density of the lower stratum.

Evaluation of Response of Different Varieties of Major Crops for Organic Farming under North Gujarat Condition

A field experiment was conducted during 2015-16 to 2021-22 at Centre for Research on IFS, S.D.A.U., Sardarkrushinagarto study the evaluation of response of different varieties of major crops for organic farming under north Gujarat condition. Total eight different varieties of each crop groundnut, wheat and green gram were taken for study during the kharif, rabi and summer season, respectively. The experiment was laid down in randomized block design with three replications. Significantly higher groundnut pod yield (1813 kg/ha) and haulm yield (2755 kg/ha) were recorded in GJG 17 (S) in pooled results and also in individual years. The significantly higher groundnut equivalent yield (2115 kg/ha), economic performance in terms of net return (82404 ₹/ha) was recorded higher in case of GJG 17 (S) as compare to other variety. In case of wheat variety, significantly higher groundnut equivalent yield (1850 kg/ha), gross return (1,18,047 ₹/ha) and net return (50,239 ₹/ha)) was recorded under GW 451, which was at par with GW 496 wheat variety. During summer season, significantly highest groundnut equivalent yield (612 kg/ha), gross return (39031 ₹/ha) and net return (9730 ₹/ha) were recorded with greengram variety GM4. There was improvement in soil nutrients status over its initial value by using the organic manure in cropping system. The percent increase in soil organic carbon was 32.6%, available nitrogen 17.3%, available phosphorus 78.9%, available potassium 5.8%.,while 21% increase in water holding capacity and 4.3% reduction in bulk density due to continuous use of organic manures as a sources. The bacterial population, actinomycetes and fungi population were increased over first year after conversion period and recorded higher in last year 2021-22 under groundnut-wheat- greengram crop sequence.

Ejected Particles after Impact Splash on Mars: Aggregates and Aerodynamics

Our earlier laboratory measurements showed that low-velocity sand impacts release fine <5 μm dust from a Martian simulant soil. This dust will become airborne in the Martian atmosphere. Here, we extend this study by measuring aerodynamic properties of ejecta and characterizing deviations from the behavior of spherical, monolithic grains. We observe the settling of particles emitted as part of an impact splash. The sizes (20 to 280 μm) and sedimentation velocities (0.1 to 0.8 m s−1) of the particles are deduced from high-speed videos while the particles sediment under low ambient pressure of about 1 mbar. The particles regularly settle slower than expected, down to a factor of about 0.3. Using optical microscopy, the shape of the captured particles is characterized by simple axis ratios (longest/smallest), which show that the vast majority of particles are irregular but typically not too elongated, with axis ratios below 2 on average. Electron microscopy further reveals that the particles are typically porous aggregates, which is the most likely reason for the reduction of the sedimentation velocity. Due to the reduced bulk density, aggregates up to 10 μm in diameter should regularly be a part of the dust in the Martian atmosphere.

Effects of Seed Germination on Physicochemical and Bioactive Compounds Characteristics of Velvet Bean Tempe

Indonesia, known as the largest tempe-producing country globally with approximately 160,000 producers, faces a challenge in meeting the demand for tempe due to insufficient local soybean supply. To address this issue, Indonesia has been compelled to import significant quantities of soybeans, reaching 1.68 million tons in 2020, which escalated by 47.78% to 2.49 million tons in 2021. This study aims to scientifically investigate the impact of velvet bean seed germination on the physicochemical characteristics and bioactive components of velvet bean tempe. The research methodology involved quantitative analysis to obtain reliable results. The preliminary analysis established that the optimal velvet bean tempe fermentation time was 48 hours. Following germination, the physical properties of velvet bean sprouts exhibited an increase in weight accompanied by a reduction in bulk density and absolute density. Furthermore, the germination treatment resulted in decreased brightness, saturation, whiteness, and pH values, while simultaneously increasing the hardness of the tempe. Chemical analysis demonstrated that germination of velvet bean seeds led to an elevation in moisture content and a decrease in carbohydrate content within the produced tempe. Additionally, bioactive component analysis revealed that the germination treatment contributed to a reduction in total phenol content from 52.46 to 36.30 mg AAE/100g, antioxidant capacity from 132.80 to 66.90 mg GAE/100g, and GABA content from 54.20 to 21.50 mg/100g in the tempe. These findings provide valuable scientific insights into alternative ingredient utilisation and production processes optimisation of velvet bean tempe.

Optimizing Sericea Lespedeza Fodder Production in the Southeastern US: A Climate-Informed Geospatial Engineering Approach

Lack of attention to rural healthcare for livestock in the southeastern United States has led to a focus on small ruminant farming, mainly using sericea lespedeza [SL; Lespedeza cuneata (Dum-Cours) G. Don], a drought-resistant forage species with nutraceutical benefits. Climate change has increased land availability for SL cultivation, further expanding the potential of this bioactive (anti-parasitic) legume. This study aims to create a geospatial engineering and technology-assisted model for identifying suitable SL production areas for supporting profitable small ruminant farming. The cultivation of SL depends on specific weather conditions and soil properties, with minimum requirements for temperature and rainfall, non-clay soil with reduced bulk density, and open land cover. The main objective was to develop an automated geospatial model using ArcGIS Pro ModelBuilder to assess SL production suitability. This model also aimed to identify appropriate locations for small ruminant production in Georgia in the southeastern United States, characterized by increasing temperature fluctuations. A web-based geographic information system (webGIS) platform was developed using the ArcGIS Online dashboard interface, allowing agriculturalists to access decision support for SL production suitability tailored to their land. This forage production suitability analysis, conducted in the context of climate change, offers valuable guidance for pasture managers in other nations with similar environmental attributes, promoting global adaptability and resilience.

Long-term effects of cover crops on physical-hydric properties of compacted soil

The screening of cover crops is essential for improving the physical-hydric properties of compacted soils. This study aimed to evaluate the effects of mixed or single cover crops on improving the physical-hydric properties of compacted Oxisol. Species with tap-rooted and fibrous-rooted rooting patterns were evaluated. The species included pearl millet (Pennisetum americanum), pigeon pea (Cajanus cajan), sunn hemp (Crotalaria spectabilis), velvet bean (Mucuna pruriens), white oat (Avena sativa), black oat (Avena strigosa), rye (Secale cereale), black oat + forage turnip (Raphanus sativus), black oat + white lupin (Lupinus albus L.), and black oat + group pea (Pisum arvense L.). Mixing cover crops did not improve the physical properties of the soil. The tap-rooted pigeon pea effectively reduces bulk density and increases porosity and saturated hydraulic conductivity (Ksat) in compact soils. The selection of cover crops with characteristics that improve soil physical-hydric properties is crucial for compacted areas.

Microplastics affect C, N, and P cycling in natural environments: Highlighting the driver of soil hydraulic properties

As microplastics (MPs) are organic polymers with a carbon-based framework, they may affect nutrient cycling. Information regarding how MPs influence N, P, and C cycling and the underlying driving force remains lacking. N, P, and C cycling induced by soil hydraulic properties under MPs exposure (including polyethylene (PE), polyvinyl chloride (PVC), polystyrene (PS), polypropylene (PP)) in the natural environment were investigated in this study. MPs exposure increased the soil water content (11.2–84.5%) and reduced bulk density (11.4–42.8%); soil saturated hydraulic conductivity increased by 7.3–69.4% under PP and PE exposure. MPs exposure led to increases in available phosphorus, NO3--N, NH4+-N, and soil organic matter; the bacterial communities related to N and C cycling were significantly changed. Expression levels of soil N and C cycling-related genes were enhanced under low concentrations (0.5% and 2%) of MPs, except PVC; consequently, soil nitrogen storage and organic carbon storage increased by 12–75% and 6.7–93%, respectively. Correlation analyses among soil hydraulic properties, bacterial communities, and functional genes related to nutrient cycling revealed that soil hydraulic properties (including soil water content, saturated water capacity, and soil saturated hydraulic conductivity) were the dominant factors affecting soil N and C storage under MPs exposure.

Reduced tillage and subsurface fertigation improve productivity and economic benefits in the cotton-wheat cropping system

Soil compaction under repetitive tillage and surface flood method of irrigation (SFMI) are significant hurdles for sustaining crop production in India, necessitating the adoption of efficient soil and water management strategies. Hence, a 3-year field study was conducted at two diverse agro-climatic locations (Abohar and Faridkot) to investigate the impact of subsurface drip (SUSD) fertigation on crop and water productivity of cotton-wheat cropping system (CWCS), over traditional practice (TP) (conventional tillage with SFMI and manual application of nutrients). The experiment was conducted in a factorial randomized complete block design with three levels of subsurface drip irrigation (SUSDI) [100, 80, and 60% of crop evapotranspiration (ETc)] and two fertigation levels [75% recommended dose of nutrients (RDN) and 100% RDN], where TP and surface drip (SD) fertigation at 80% ETc coupled with 100% RDN (Control 2), served as two control treatments. Cotton was raised through reduced tillage, while zero till drill was used for sowing wheat. The results revealed that, barring SUSDI at 60% ETc, both crops exhibited improved yield under all drip combinations of reduced or zero tillage over TP. Better mass and higher length of cotton roots in drip fertigation were evident due to improved steady-state infiltration rates (SSIR) and reduced bulk density (BD) under conservation tillage. When 100% RDN was applied, the 100% and 80% ETc SUSDI resulted in 26.7% and 24.7% higher seed cotton yield (SCY) than TP. Similarly, wheat yield with 100% RDN was improved by 10.5% and 14.4% under SUSDI of 80% and 100% ETc, respectively, over the TP. The results indicated that SUSD can be clubbed with reduced tillage for better soil health, improved crop yield, and higher apparent water productivity. The improved benefit to cost (B:C) owing to enhanced monetary returns over TP also substantiated that reduced tillage with SUSD is a viable and remunerative practice for CWCS. The study elucidated that reduced tillage exercised a beneficial effect on physical soil properties by lowering BD and improving SSIR. At the same time, SUSD could save huge amounts of irrigation water besides enhanced input use efficiency leading to higher crop productivity.

Drought Stress Modulation by Biochar and Effects on Soil and Performance of Seedlings of Urban Forest Tree Species

Aims: This study was designed to examine the effects of watering regime and biochar on soil properties and performance of seedlings of urban forest tree species (UFTS) in the nursery. Study Design: The experiment was a 5 by 3 by 2 factorial scheme involving urban forest tree species, watering regimes and biochar amendment or not. Place and Duration of Study: seedlings of five UFTS were raised in the Nursery and Screenhouse of Wesley University, Ondo, a rainforest zone of Nigeria. Methodology: Seedlings of five Urban Forest Tree Species (UFTS) were subjected to watering at 80, 60 and 35% field capacity (FC) with or without biochar amendment. UFTS evaluated are: Bauhinia monandra, Delonix regia, Terminalia catappa, Dypsis lutescens and Veitchia merrillii. Results: Watering regime and biochar amendment exerted significant effects on soil physical and chemical properties, physiological attributes and biochemical constituents and performance o the UFTS evaluated. Watering at 60 and 35% FC increased bulk and particle densities but reduced significantly (P&lt;.05) soil moisture content at field capacity compare with watering at 80% FC. Further, the 60 and 35% FC watering exhibited low N, available K+, Ca2+ and Mg2+. Addition of biochar to the variously watered soil considerably reduced bulk density but remarkably increased porosity, field capacity moisture and plant available moisture. Biochar amendment increased soil pH, total and volatile organic matter contents, available K+ and Ca2+, extractable Mg2+ and dissolved phosphate (PO43+). The responses of growth traits and biochemical constituents of UFTS to watering regimes was species specific. Relative to 80 % FC watering, seedling growth attributes reduced significantly under deficit water application (60 and 35% FC) in addition to remarkable accumulation of osmolytes (osmoprotectants) and enzymatic activities. Biochar amendment enhanced accumulation of osmolytes and activities of superoxide dismutase, guaiacol peroxidase and catalase enzymes of UFTS seedlings. Conclusion: Differential watering and biochar amendment affected soil physical and chemical properties and growth of UFTS seedlings evaluated. Biochar amendment of the variously watered soil enhanced seedling growth, and appear as effective strategy for improving soil properties and UFTS performance, and for mitigation of adverse effects of suboptimal watering.

Biochar as a carbonaceous material to enhance soil quality in drylands ecosystems: A review

Drylands are fragile environments that should be carefully managed to improve their quality and functions to achieve sustainable development. Their major problems involve low availability of nutrients and soil organic carbon content. Biochar effect on soil is a joint response of micro to nano sized biochar and soil characteristics. In this review, we attempt to carry out a critical analysis of biochar application to enhance dryland soil quality. Correlating the effects identified from its soil application, we explored the subjects that remains open in the literature. The relation of composition-structure-properties of biochar vary among pyrolysis parameters and biomass sources. Limitations in soil physical quality in drylands, such as low water-holding capacity, can be alleviated by applying biochar at a rate of 10 Mg ha−1 also resulting in beneficial effects on soil aggregation, improved soil porosity, and reduced bulk density. Biochar addition can contribute to the rehabilitation of saline soils, by releasing cations able to displaces sodium in the exchange complex. However, the recovery process of salt-affected soils might be accelerated by the association of biochar with another soil conditioners. This is a promising strategy especially considering the biochar alkalinity and variability in nutrients bioavailability to improve soil fertilization. Further, while higher biochar application rate (>20 Mg ha−1) might change soil C dynamics, a combination of biochar and nitrogen fertilizer can increase microbial biomass carbon in dryland systems. Other aspect of biochar soil application is the economic viability of scale-up production, which is mainly associate to pyrolysis process being biochar production the costliest stage. Nevertheless, the supplying of feedstock might also represent a great input on biochar final costs. Therefore, biochar-based technology is a big opportunity to improve fragile environments such as drylands, integrating sustainable technologies with regional development. Considering the specificity of application area, it might be a model of sustainable agricultural practices protecting the environment in a bioeconomic perspective.

Biochar derived from papermill factories improves soil physical and hydraulic properties in no-till cotton fields

Whether biochar produced as a by-product of energy generation from the papermill industry, and often disposed in landfills, can be gainfully applied to commercial croplands has not been investigated. The objective of this study was to investigate the physical and hydraulic properties of soils in commercial cotton fields managed as no-till systems following repeated applications of biochar generated as a waste of a papermill plant. Undisturbed cores and disturbed soil samples were collected from 0–5 and 5–10 cm layers from five commercial no-till fields in Mississippi, USA that received 6.7 Mg ha−1 year−1 biochar for 0, 2, 3, 5 or 10 years. A number of physical, hydraulic, and chemical properties of these samples were measured in the lab. The results showed that biochar reduced the degree of soil compactness and increased soil aggregation and structural stability index. The findings were particularly apparent for the 10 years of consecutive application, which increased soil aggregate stability by up to 67%, reduced bulk density from 1.40 to 1.26 g cm−3, and reduced degree of compactness from 73.2% to 62.8%. Biochar increased soil porosity but much of this increase (55%) occurred for small pores (< 0.5 μm) with little effect on storage pores (0.5–50 μm) or transmission pores (> 50 μm). Consequently, biochar increased soil field capacity by up to 26%, but PAW increased by only 17%. Biochar significantly increased soil physical quality index score in the 0–5 cm layer from 0.16 to 0.26 and the increase was positively correlated with the number of years of application. The results suggest biochar generated as a byproduct of papermill could be land-applied in real-world crop production systems to improve soil health as an alternative to disposal in landfills.Graphical

Forage Radish Cover Crops Improve Soil Quality and Fruit Yield of Lycium barbarum L. in an Arid Area of Northwest China

Intercropping orchards with cover crops is an important practice for achieving sustainable soil management. However, little research has addressed the development of a soil quality index (SQI) to evaluate cover crop effects on orchard soil quality. The aim of this study was to ascertain whether cover cropping improves soil quality and fruit yield of Goji (Lycium barbarum L.) while reducing or replacing organic fertilizer application. The main treatments were the traditional management of L. barbarum as a monocrop (M) and intercropping Goji with radish (Raphanus sativus L.) as an annual cover crop (I). Within the main treatments, different levels of organic fertilizer were applied at 0 kg·plant−1 (M0), 2 kg·plant−1 (M1), and 4 kg·plant−1 (M2). After six years of planting, we analyzed the changes in soil quality caused by cover cropping with different organic fertilizer levels based on the SQI method. Goji yields were used for validation of the SQI derived from a minimum data set of soil quality indicators. In contrast with traditional monocropping, cover cropping increased soil total nitrogen, available nitrogen, and available phosphorus contents (by 78.60%, 30.30%, and 138.08%, respectively). There were also increased microbial biomass carbon and nitrogen contents (by 79.01% and 184.01%, respectively), enhanced urease and sucrase activities (by 41.02% and 56.81%, respectively), and reduced bulk density (by 1.92%) in the soil as a result of cover cropping. Compared with IM0 treatment, soil microbial biomass carbon and nitrogen contents considerably increased under IM1 treatment, whereas soil available nitrogen and potassium contents as well as electrical conductivity increased under IM2 treatment. The SQI, which varied among treatments in the order IM1 &gt; IM2 &gt; MM2 &gt; MM1 &gt; IM0 &gt; MM0, was positively correlated with Goji yield. From the soil quality and Goji yield perspective, cover cropping with a medium level of organic fertilizer is the optimal soil management practice for the L. barbarum planting system in arid areas of Ningxia, Northwest China.

Integrated Management Practices for Canopy-Topsoil Improves the Grain Yield of Maize with High Planting Density.

Inappropriate spatial distribution of canopy and roots limits further improvements to the grain yield of maize with increased planting density. We explored an integrated management practice called strip deep rotary with staggered planting (SRS) which includes comprehensive technology for both canopy layers and topsoil. Here, field experiments were conducted under two maize cropping systems (spring maize and summer maize) to evaluate the effect of SRS on the spatial distribution of the canopy and roots for maize under high planting density (90,000 plants ha-1) and to determine the physiological factors involved in yield formation. Compared with conventional management practices (no-tillage with single planting, NTS), SRS decreased the LAI of the middle to top layers while improving the light distribution of the middle and lower layers by 72.99% and 84.78%, respectively. Meanwhile, SRS increased the root dry weight density and root sap bleeding by 51.26% and 21.77%, respectively, due to the reduction in soil bulk density by an average of 5.08% in the 0-40 cm soil layer. SRS improved the SPAD in the ear and lower leaves and maximized the LAD, which was conducive to dry matter accumulation (DMA), increasing it by 14.02-24.16% compared to that of NTS. As a result, SRS increased maize grain yield by 6.71-25.44%. These results suggest that strip deep rotary combined with staggered planting noticeably optimized the distribution of light in the canopy and reduced the soil bulk density to promote root vitality and growth, to maintain canopy longevity, and to promote the accumulation of dry matter, which eventually increased the grain yield of the maize under high planting density conditions. Therefore, SRS can be considered a better choice for the sustainable high yield of maize under high-density planting conditions in the NCP and similar areas throughout the world.

Hydro-physical deterioration of a calcareous clay-rich soil by sodic water in Central Anatolia, Türkiye

The deleterious effects of sodium-induced secondary alkalinization on soil structure and hydraulic properties of calcareous soils can vary widely. This study aims to evaluate the impact of sodicity and leaching velocity on the physical and hydraulic properties of a calcareous clay-rich soil. Two application rates of tap water (TW) and sodic water (SW) are considered: fast leaching, equal to the saturated hydraulic conductivity, Ks, and slow leaching conditions, equal to have 1/2 Ks. For the TW and SW experiments, up to 14 and 26 leaching cycles were performed in duplicates, respectively. After the leaching applications, the PVC columns were cut horizontally, and undisturbed samples were removed from the different depths. It was observed that neither water quality nor water flow rate significantly affected water stable aggregate percentages. TW did not affect soil total porosity and bulk density except at the bottom of the column. On the other hand, there were remarkable reductions in soil porosity and bulk density in the SW leaching experiments ranging from 8.8 to 12.5% and 7.4–13.8%, respectively. High Na concentrations in leaching water caused aggregate swelling and dispersion, leading to reduced Na+ and enhanced Ca2+ transport to the lower portions of the soil column. In the lower layers, the severity of sodium-induced dispersion was restricted by calcium, which was exchanged by the excess amount of Na from the upper layers, maintaining soil particles flocculated. Ca2+, which tightens the soil particles and aggregates together, limited Na-induced disruption of the soil aggregation. Nonetheless, particles that broke away from aggregate did influence the hydraulic properties of the soils. Overall, the experiments revealed that although the physical and hydraulic properties of the soil are affected by the sodic waters and the flow rates, this effect is reduced in calcareous soils due to their strong bonding feature.

Recycling argan nut shell and wheat straw as a porous agent in the production of clay masonry units

The present work aims to study and compare the effect of incorporating argan nut shell (ANS) and wheat straw (WS) into clay mixtures as construction materials additives on physical, mechanical, structural, and thermal properties of fired clay bricks. Five clay mixtures were prepared, including a control sample free of waste, two clay samples containing 5 wt% and 10 w.t% of ANS (ANS5 and ANS10), two others containing 5 wt% and 10 wt% of WS (WS5 and WS10), all specimens were fired at 900 °C, and their technological properties in term of loss on ignition, firing shrinkage, water absorption, apparent porosity, bulk density, flexural strength, compressive strength, and thermal conductivity were evaluated. A reduction in bulk density and thermal conductivity has been observed with the incorporation of ANS and WS, leading to an increment in the apparent porosity and water absorption in their turn, which is typically due to the specimen’s porous structure. The thermal conductivity of clay brick samples containing 5–10 wt% of ANS or WS decreased by 5–17% and 27–46%, respectively. Thus, the thermal insulation property is improved while the mechanical properties (flexural and compressive strength) meet the requirements of the standards for clay masonry units, except for WS5 brick. Test results highlighted the potential of recycling ANS and WS in clay masonry units and thus, the production of lightweight material.

Soil Physical Properties as Influence by Poultry and Cow Dung from Different Housing and Stacking Types Following Telfairia occidentalis (Hook F.) Production

Soil physical properties play significant function in the yield of crop produce. Sustaining food supply of the teeming population depends on the degree of preserving soil physicalproperties, therefore enhancing soil productivity. Experiments were conducted to establish the influence of poultry and cow dung from different housing and stacking types on physical properties of soil following Telfairia occidentalis production in 2017 and 2018. Amendments were applied in both years after which data were analyzed using Analysis of Variance. The experiment reveals that amendments statistically increased soil porosity, moisture content, hydraulic conductivity and therefore reduced bulk density above control in both years. It is concluded that for improved soil physical properties in the study area, bagged poultry manure in palm fronds house (PPB) at 5.4 tha-1 is recommended to farmers.

Biochar Amends Saline Soil and Enhances Maize Growth: Three-Year Field Experiment Findings

Soil salinization is a significant obstacle to agricultural development in arid and semiarid regions. While short-term experiments have demonstrated the effective improvement of saline soils through biochar amendment, the long-term efficacy in sustainably ameliorating such soils remains uncertain. Addressing this knowledge gap, this study investigated the long-term effects of biochar amendment in a field setting by applying different rates of biochar to a salt-affected soil and cultivating silage maize for three consecutive years. The comprehensive assessment includes not only maize growth but also changes in soil physical and chemical properties over the study period. The results reveal a notable elevation in maize above-ground dry matter, directly correlated to the enhanced uptake of nitrogen, phosphorous, and potassium. Additionally, biochar application improves saline soil physical properties, including reduced bulk density (1–23%), increased soil large pores (0.7–12%), and macroaggregates (24–141%), and chemical properties, including a decrease in exchangeable sodium percentage (35–48%), and an increase in soil total organic carbon (112–857%), total nitrogen (9–198%), available nitrogen (12–49%), phosphorus (141–538%) and potassium (57–895%). These improvements ultimately resulted in better maize growth. However, the amelioration effect of biochar on these soil properties gradually diminished over the three-year study. Consequently, this study suggests that biochar is a promising soil amendment that can enhance maize growth in saline soil for at least three years in a field experiment, providing valuable insights for sustainable agricultural practices in salt-affected regions.