Hill Soils Research Articles

Evaluation of the microstructural and physico-mechanical characteristics of cement-stabilized termite hill soil for construction application

This study investigates the potential of termite hill soil (TS) as an environmentally friendly alternative to cement. By reducing reliance on cement, this approach could decrease the environmental footprint of the construction industry. Portland cement was used to stabilize TS at contents of 5%, 10%, and 15% by weight (wt%). Key engineering properties of the stabilized and un-stabilized specimens were analyzed to assess the suitability of TS for construction applications. Physical properties were evaluated using particle size distribution analysis, dimensional stability testing, and density measurements. Microstructural analysis employed Scanning Electron Microscopy (SEM) coupled with Energy-Dispersive X-ray spectroscopy (EDX), Fourier Transform Infrared (FTIR) spectroscopy, and X-ray fluorescence (XRF) to investigate the effects of stabilization on the microstructure and its influence on bulk properties. Compressive and flexural strength tests were conducted to assess the mechanical properties of the specimens. Compressive strength results showed that the 10–15 wt% stabilization level achieved the highest values, reaching 3.81 MPa, 4.58 MPa, and 5.91 MPa at 7, 14, and 28 days, respectively. Flexural strength values for the same specimens at these curing times were 0.98 MPa, 1.72 MPa, and 1.94 MPa, respectively. The findings of this investigation can serve as a reference for treating other soils to achieve properties similar to TS, making them suitable for durable construction applications. Additionally, this study demonstrates the feasibility of developing and using TS as construction material for housing solutions in regions with abundant and currently undervalued termite hill resources.

Assessing horticulture-based land management impacts on carbon dynamics and soil quality

The present study was carried during 2020 and 2021 at School of Agricultural Sciences and Rural Development (Nagaland University), Medziphema, Nagaland to study the effects of different horticulture-based land use systems on carbon stock, soil fertility and soil biological health in acidic hill soils of Nagaland. Average values of bulk density of the soils were 1.20 and 1.21 g/cm3 in surface and sub-surface soils, respectively irrespective of type of orchards. The maximum and minimum carbon stock was recorded in pineapple [Ananas comosus (L.) Merr.] (46.77 and 43.38 mg/ha) and citrus (Citrus spp.) (33.07 and 32.42 mg/ha) orchard soils. Soil microbial biomass carbon in pineapple (270.13 and 244.23 µg/g) and citrus orchard soils (165.64 and 152.49 µg/g) was recorded in surface and sub-surface layers, respectively. Banana (Musa spp.) orchard soils had greater values of dehydrogenase activity (15.26 and 9.83 µg TPF/g/h). Soils of banana orchard also recorded highest acid phosphatase activity (176.0 and 165.5 µg PNP/g/h), which was at par with mango (Mangifera indica L.) orchard soils (175 and 166 µg PNP/g/h). Minimum acid phosphatase activity (162.0 and 150.0 µg PNP/g/h) was recorded in citrus orchard soils. Maximum earthworm population density was recorded in banana orchard (12–20 number/m2) and minimum (4–12 number/m2) in citrus orchards.

Effects of Different Soil Amendments on Growth, Yield and Nutrients Uptake of Stem Amaranth in Acidic Alluvial-and-Hill Soils in a Subtropical Area

ABSTRACT Sandy and acidic soil conditions are the major factors limiting the production of some vegetable crops in acidic soils. This study aims to examine the effect of various amendments on the growth, yield and mineral nutrients uptake of stem amaranth. Two pot experiments were conducted separately in two generic soils. Six treatments viz. T0 = control (without amendment), T1= lime, T2 = lime + wetland bottom sediment, T3 = lime + vermicompost, T4 = lime + rice straw biochar (RSB) and T5 = RSB were used for both experiments following CRD with four replications. Results revealed that plant heights (45.96 and 50.33 cm) of amaranth grown in alluvial and hill soils, respectively, were the highest in T4 treatment. Similarly, treatment T4 showed the highest fresh (118.53 and 116.11 g pot−1, respectively) and dry biomasses (16.98 and 19.54 g pot−1, respectively) for both soils. For both soils, treatment T4 resulted better nutrient uptake of N, P, K, S, Zn, Fe and Mn by edible stem, while non-amended soil gave the lowest result at all parameters. Analytical values of post-harvest soils indicated that T4 and/or T5 treatments resulted in an improvement in soil pH, organic carbon, total N, exchangeable K and extractable P, S and Zn. Treatment T3 showed elevated concentrations of extractable soils Fe and Mn. The amendment RSB combined with lime can be preferably used in strong acidic soils for cultivation of stem amaranth.

Response of scented rice landraces of North Bengal under organic nutrient management in Darjeeling hills

The traditional practice of growing scented rice in Darjeeling Himalayas needs refinement in nutrient management for sustained production with desired quality. The effect of organic nutrient sources (Cow dung manure @ 5 t/ha, Vermicompost @ 1.5 t/ha, Mustard cake @ 0.5 t/ha, and Leaf mould @ 1 t/ha) on two aromatic rice cultivars (Kalture, and Kalonunia) was studied in a split-plot design during wet (kharif) season of 2021 at Uttar Banga Krishi Viswavidyalaya, Kalimpong, West Bengal. Kalture had taller plants (137.1 cm) and lodging susceptibility (score 4.0) at harvest, while Kalonunia remained unlodged. Kalonunia produced 16.1% greater grain yield (3.32 t ha-1 vs. 2.86 t ha-1) over Kalture due to more number of panicles m-2 (356.2) and filled grains panicle-1 (90.1). Both aromatic rice cultivars had medium-slender (MS) white kernels, but Kalonunia had higher protein content (7.3%), alkali spreading value (score 6.0) and aroma (score 1.8) than Kalture (6.7%, score 5.7 and score 1.6). The application of vermicompost @ 1.5 t ha-1 resulted in higher grain yield (3.22 t ha-1), but mustard cake @ 0.5 t ha-1 might be better option due to moderate yield (3.11 t ha-1), better grain quality, and greater residual N (235.1 kg ha-1), P status (23.4 kg ha-1) in hill soil of West Bengal.

A facies- and sequence stratigraphy-based reservoir model for a carbonate reef complex: South Swan Hills oil pool, Alberta

We present a reservoir model for the South Swan Hills oilfield, Alberta, Canada, developed in a Devonian atoll reef, based on facies analysis and sequence stratigraphy. The analysis illustrates the complex reservoir geometries in such a reef, caused by facies variation from reef margin to reef interior and fluctuations in relative sea level. The latter resulted in cyclic deposition of facies and formation of field-scale sequence boundaries. The model is built on lithofacies analysis from high-resolution core descriptions that recorded lithologies, bioclast type and characteristics, and sedimentary structures. Core descriptions were correlated to well logs, enabling lithofacies to be mapped across the field. Lithofacies distributions permit definition of three distinct reef environments: a reef interior, a reef margin and a terminal shoal. Vertical variability is characterized using sequence stratigraphic interpretations. Two 3rd order and four 4th order sequence boundaries were identified and correlated across the reef. The analysis illustrates the complex reef geometries linked to facies variation from reef margin to reef interior and fluctuations in relative sea level. The latter resulted in cyclic deposition of facies and formation of field-scale unconformities. These and the intervening deposits represent the response to fluctuating sea level.The geological analysis was transformed into a 3-D geocellular model using a sequential indicator simulator. The simulator models lithofacies and, in turn, porosity and permeability distributions based on strong relationships between lithofacies and petrophysical properties for the three representative regions; the interior, margin and terminal shoal. The interior deposits formed forms the bulk of non-reservoir material in the centre of the reef build-up. The margin surrounded surrounds the interior and formed forms a continuous 1–2 km band of reservoir around it. Reservoir thickness is 20–30 m and primarily composed of reef flat deposits. The terminal shoal forms a reservoir body that caps the reef complex, but is disconnected from the bulk of the underlying reef by a thick layer of impermeable clay associated with a sequence boundary. The high-resolution realization displays the geometry and continuity of the reservoir and exposes demonstrates the compartmentalized and variable producibility of the atoll.

Maize Grain Quality as Influenced by Chemical, Organic and Natural Farming Systems in an Acid Hill Soil of North-Western Himalayas

Maize Grain Quality as Influenced by Chemical, Organic and Natural Farming Systems in an Acid Hill Soil of North-Western Himalayas

SPT Based Liquefaction Potentiality Index, Susceptibility & Risk Assessment in the Rohingya Refugee Camp Hills of Ukhiya, Cox’s Bazar, Bangladesh

More than one million Rohingya refugees who fled from Myanmar, had constructed temporary shelters on the loose unconsolidated sandy hills (SC-SM, SP & ML) of Ukhiya-Teknaf region, Cox’s Bazar area, Bangladesh. After entering Bangladesh, the green eco forests of Ukhiya Hills had to be destroyed by cutting trees and hill slopes as they built their shelters which eventually had destructive effects on the ecosystem of Ukhiya Teknaf region. Sands (SP-SM) are mainly uniformly graded and composed of more than 72% to 98 % sand. This research has been carried out to assess the liquefaction potentiality index vales, susceptibility using SPT and risks associated with the Ukhiya hills at different earthquake magnitudes. During earthquake at Magnitudes 5 or greater, Ukhiya hill soils are susceptible to liquefy up to a depth of 12 m.. From the Liquefaction Potentiality Index (LPI) values, risk and sensitivity analysis, it is established that the Ukhiya hills are medium to highly susceptible to liquefy at higher magnitudes (M= 5 or greater). It is also established that north western part of the camp hills are high to very high risk prone areas. Based on Liquefaction Potentiality Index (LPI) values, four seismic risk zones are identified in and around the Rohingya camp area. Some geo-engineering recommendations are also made to reduce this seismic hazard for sustainable community living in the camp area.

Comparative Study of Nutrient Release Pattern from Nutripellet Pack and Polycoat Paper Encapsulated Fertilizer Pack Placed in Soils

Nutripellet pack is a tubular assembly composed of fertilizer pellet, manure pellet and bioinoculants. A laboratory electrolyte release study was conducted to assess the extent of nutrient enrichment by nutrient release from encapsulated fertilizer pellet. Nutripellet pack and fertilizer pellet pack was placed in soil, within a closed container. Periodically the entire soil was removed for the estimation of soil reaction (pH), electrical conductivity (EC) and available forms of N, P and K up to 11 weeks after incubation (WAI). Before the analysis the residual encapsulated pellet was removed. The treatments comprising the sources of fertilizers (N for urea, P for DAP or SSP and K for MOP), levels of nutrient release pore (0, 25 micro pores) in fertilizer pellet and Nutripellet pack (fertilizer pellet + manure pellet) placement in sand, red soil and hill soil. High available N, P and K observed with Nutripellet pack with NP (DAP) K was registered in sand, red and hilly soils.

Soils of the Central Nebraska Loess Hills and Central Loess Plains

Soils of the Central Nebraska Loess Hills and Central Loess Plains

Pedological Development of Soils in Eastern Agroclimatic Zone of Haryana through Field Morphology Rating System

A study was carried out to evaluate the pedological development of soils in Eastern agroclimatic zone of Haryana using field morphology rating system. For this, nine pedons were excavated to study the morphological properties in field and rating scale was used to compare adjacent horizons with each other to give a comparison of the relative distinctness of horizons or to compare horizons in the solum with the C-horizon to give a relative profile development in soils occurring in different physiographic positions i.e. Shiwalik hills, recent and old alluvial plains with different precipitations throughout the study area. Some chemical properties were also used to evaluate the pedogenic factors as a result of being affected by process and factors of soil formation due to the distinct effect of climate. The Relative Horizons Distinctness (RHD) ratings were made by a comparison of adjacent horizons. The soils of Shiwalik hills, recent and old alluvial plains have RHD ratings from 6 to 14, 3 to 11 & 3 to 12, respectively. The RPD ratings were made by a comparison of the C horizon to the horizons above it in the profile. The soils of Shiwalik hills, recent and old alluvial plains have RPD ratings from 7 to 15, 3 to 14 & 5 to 16. The RPD values of all the profiles were maximum in A horizon due to maximum pedological development influenced by weathering. So, studies of these soils indicated the pedological development in the order of Shiwalik hills > old alluvial plains > recent alluvial plains.

Microplastic contamination of coastal hill soils: Perspective of Rohingya Refugee camps in Bangladesh

ABSTRACT Microplastics (MPs) pollution of environments due to human activities is a global concern. In the present study, we examined the occurrence of MPs in coastal hill soils (burned and non-burned) collected from the Rohingya Refugee camps in Cox’s Bazar, Bangladesh. The total number of MPs per kg of burned soil (402–403 items/kg) sample was significantly higher than that in non-burned soil (210 items/kg) sample. Fibers (24–57%) dominated in all the samples, followed by fragments (18–51%), sheet (12–29%), and microbeads (12–13%). The most common color of MPs was blue (16–68%), followed by red (14–25%), transparent (14–24%) and brown (14–22%). Among the size groups, MPs of 0.5-<1.0 mm (34–44%) dominated in all the samples, followed by 1.0–5.0 mm (27–45%) and <0.5 mm (14–29%). Attenuated Total Reflectance Fourier Transform Infrared spectroscopy analysis confirmed the most abundant polymer type in burned soil was polystyrene (28%) followed by polypropylene (23%), polyethylene (21%), polyamide (15%), ethylene-vinyl acetate (8%), and polyvinyl chloride (3%). The study confirms the presence of high MPs loads in burned soil, with high potential of trophic transfer to plants and washed out to aquatic environment and will appear as base line information for further assessment of MPs effects on biota.

Application of Dragon Fruit Peel’s Mucilage in Coagulation – Flocculation Process to Remove Turbidity from Water

The study determined flocculation activity of mucilage extracted from dragon fruit peel (Hylocereus undatus) and its ability in reducing synthetic coagulant polyaluminium chloride (PAC) used in coagulation – flocculation process to remove turbidity of different types of water. Investigated waters were turbid waters made from kaolin suspension (KS), suspension of river water with hill soil (FW), and To Lich river water (TL). Turbidity removal was assessed in a sequent coagulation and flocculation model using PAC and mucilage extracted from dragon fruit peel in Jar-tests. Optimal coagulation conditions of PAC with PAC dosage of 20-50 mg/L and pH range of 6-8 regardless of water types and resulted in maximum turbidity removal of about 98%. In order to obtain a comparable turbidity removal, 50%-68% of the required PAC was reduced if mucilage was used. The presence of mucilage enhanced turbidity removal of PAC by 13-22% total efficiency. Mucilage extracted from dragon fruit peel has shown its flocculation ability and its potential as a green material in water treatment.&#x0D; &#x0D; &#x0D;

Dimensionnal stability and strength appraisal of termite hill soil stabilisation using hybrid bio-waste and cement for eco-friendly housing

Dimensional stability and compressive strength are key factors to consider when modelling earth-based materials. It defines the volumetric performance of earth-based materials upon wet and dry environment. Meanwhile, the deformation under compression loading is accessed with the compressive strength testing. This study is aimed to use locally available materials considered as waste to model sustainable construction materials through soil stabilisation technique. The utilization of biowaste in this study is aimed to reduce the amount of waste produced in the agricultural sector in addition to the promotion of this material locally in the construction field. Cement was used as stabilizer to establish the performances of the waste-based stabilizer when mixed with conventional stabilizer or partnerless. Borassus fruit ash and cement were used both in solo, and hybrid mix (5wt%, 10wt%) to stabilize termite mound soil in the mix design. The mix design was analyzed microstructurally with scanning electron microscopy (SEM)-energy dispersive spectroscopy (EDS) to understand the effect of each stabilizer on the microstructural level. Fourier transform infra-red (FTIR) was conducted to identify the functional group present in each mix design to establish the influence of both stabilisers on the bonding mechanism. The mix design was also tested for water sensitivity, linear shrinkage, and compressive strength. From the results, samples containing 10wt% hybrid borassus fruit ash/cement exhibited higher content of Silicon, Aluminum, and Iron consequently satisfactory compressive strength. For hybrid stabilisation of earth-based materials, preference is given to 10wt% stabilisation level. The results of this study are analyzed to reduce the footprint of agricultural waste and to model locally available materials into sustainable housing materials.

Mapping aquifer salinity gradients and effects of oil field produced water disposal using geophysical logs: Elk Hills, Buena Vista and Coles Levee Oil Fields, San Joaquin Valley, California.

The effects of oil and gas production on adjacent groundwater quality are becoming a concern in many areas of the United States. As a result, it has become increasingly important to identify which aquifers require monitoring and protection. In this study, we map the extent of groundwater with less than 10,000 mg/L TDS both laterally and vertically near the Elk Hills, Buena Vista and Coles Levee Oil Fields in the San Joaquin Valley, California and note evidence of effects of produced water disposal on salinity within the Tulare aquifer. Subsurface maps showing the depth at which groundwater salinity is less than 10,000 mg/L (or Base 10K) in the Tulare aquifer are generated using geophysical logs and verified by comparison to water sample analyses. The depth to Base 10K ranges from 240 m (800 ft) in Elk Hills to 800 m (2650 ft) in the adjacent Buena Vista syncline and is 670 m (2,200 ft) deep in the Coles Levee area to the east. Log-calculated salinities show a relatively smooth increase with depth prior to disposal activities whereas salinities calculated from logs collected near and after disposal activities show a more variable salinity profile with depth. The effect of produced water injection is represented by log resistivity profiles that change from low resistivity at the base of the sand to higher resistivity near the top due to density differences between the saline produced water and the brackish groundwater within each sand. Continued post-disposal logging in new wells in the 18G disposal area on the south flank of Elk Hills shows that injected water has migrated approximately 1,200 m (4,000 ft) downdip (south) over a period of 20 years since the inception of disposal activity.

Response Surface MethodologyBased Optimization, Partial Purification and Characterization of Alkaline Phosphatase Isolated from Pseudomonas asiatica Strain ZKB1 and its Application in Plant Growth Promotion.

The present study was defined to evaluate the effect of a combinational approach of applying phosphate-solubilizing bacteria and alkaline phosphatase for plant growth promotion as a novel strategy. An extracellular phosphatase producing novel Pseudomonas asiatica strain ZKB1 was isolated from ant hill soil. Alkaline phosphatase production was statistically optimized by Plackett-Burman and central composite designs with a yield of 42.45 U/ml and 5.88-fold enhancement. Alkaline phosphatase was purified by column chromatography (DEAE-Cellulose and Sephadex G-100) with 17.55-fold purification and specific activity of 87.77 U/mg. The molecular mass of purified phosphatase was ~ 45kDa. The optimum pH and temperature were 9.0 and 50°C, respectively, revealing alkali-thermostability. Phosphatase exhibited the highest specificity toward p-nitrophenyl phosphate disodium salt. Kinetic analysis revealed Km (0.434mM) and Vmax (264.44 U/mg). Alkaline phosphatase and Pseudomonas asiatica strain ZKB1 as phosphate-solubilizing bacteria were assessed for their ability to induce plant growth in pot experiments with Phaseolus mungo seeds. Seeds soaked in bacterial culture broth and irrigated with increased phosphatase concentration demonstrated better growth with plumule and radical length of 14.8 ± 0.2cm and 3.5 ± 0.4cm, respectively. Results were consistent with the combinational approach in terms of enhanced growth. The study suggests the application of alkaline phosphatases in agricultural management, crop improvements, and soil fertility enhancement.

Complete Genome Sequence of Bacteriophage Fizzles, Isolated from Microbacterium foliorum.

ABSTRACTMicrobacteriophage Fizzles has a 62,078-bp linear double-stranded DNA genome sequence, predicted to contain 104 protein-coding genes. Fizzles is a Siphoviridae actinobacteriophage isolated from an ant hill soil sample collected in Stephenville, TX. Microbacteriophage Fizzles has >83.6% nucleotide identity with microbacteriophages Squash and Nike.

Bituminous substances in soils of Baikal Rift zone

Parameters of hydrocarbon complex of the soils of lacustrine-alluvial plain and sandy uplands of the Baikal rift zone within the Barguzin Depression have been studied. Data were obtained on organic (non-carbonate) carbon, chloroform and hexane bitumoids, as well as on individual polycyclic aromatic hydrocarbons. The content, composition and properties of bitumoids vary depending on the intensity of endogenous activity. In soils located in the zone of active unload of hydrothermal waters and hydrocarbon fluids, atypical accumulation of organic carbon was noted; the concentrations of bitumoids do not correlate with its content. High values of the bitumoid coefficient, significant level of polycyclic aromatic compounds and their diversity, in combination with salts accumulation, indicate an additional influx of hydrocarbons and instability of the soil hydrocarbon system. The level of the indicators shifts towards background values in the soils of sandy hills with a complex combination of exogenous and endogenous factors of soil forming. Studied parameters of the soil hydrocarbon system in aggregate can serve as markers of the intensity of endogenous processes.

A Facies- and Sequence Stratigraphy-Based Reservoir Model for a Carbonate Reef Complex: South Swan Hills Oil Pool, Alberta

A Facies- and Sequence Stratigraphy-Based Reservoir Model for a Carbonate Reef Complex: South Swan Hills Oil Pool, Alberta

Soil properties and carbon stock along the toposequence of Lalmai hill ecosystem of Bangladesh

A study was carried out in the Lalmai hill ecosystem of Bangladesh regarding their soil properties and soil organic carbon (SOC) stocks. The Lalmai hill ecosystem consists of three toposequence arrangements as hills, piedmonts, and floodplains. Forty-five soil samples covering nine soil profiles were selected to conduct the present study. Soil samples were collected at five different depths of 0-20 cm, 20-40 cm, 40-60 cm, 60-80 cm and 80-100 cm intervals from each pit of the study sites. Soil pH, percent SOC, percent total nitrogen (TN), bulk density, cation exchange capacity (CEC), particle size distribution, and SOC storage (kg/m2) dataset indicates that piedmont deposits and floodplain soils are more enriched than the upper hill soils. Regarding SOC storage, the post hoc test indicates that hill soils are significantly different from the other two physiographic units, but there is no significant difference between piedmont deposits and floodplain soils. The soil property varies differently depending on their depth level at different physiographic units. Estimation on SOC stock revealed that 2.01Tg, 21.75Tg, 12.68Tg carbon remains in the hill soils, piedmont soils, and estuarine floodplain soils, respectively. The total SOC stock was estimated at 36.44 Tg in the Lalmai hill ecosystem of Bangladesh, where piedmont deposits contained the highest level of SOC stock. It is assumed that more clay-organic substances are washed in at the foot of piedmont units due to the well-drained nature of upper Pleistocene hill soils. Thus, fine soil textural nature, diverse land and land cover accelerates to sequester more carbon in piedmont zone rather than hill or floodplain zones.&#x0D; Dhaka Univ. J. Biol. Sci. 30(2): 331-343, 2021 (July)

Covid 19 Pandemic: Misery of Local Farmers in Darjeeling Hills

India had made an early move to constrain the spread of COVID 19, requesting a 21 day across the country lockdown for its population 1.3 billion persons beginning March 25th 2020. The progressing wellbeing emergency had influenced various society including agriculture and farming. This paper represents the effect of lockdown on hill agriculture especially the agricultural business performed by the native peoples of Darjeeling hills who are basically the daily labours. Soils of hills are not suitable for performing agriculture so easily like plain lands and non-application of synthetic pesticides makes hill agriculture so tough. The survey work was divided into two parts one containing period before the lockdown and another lockdown period as well as the unlock phases. Outcome of this report reveals that there was a significant loss to the farmers during the lockdown and unlock phases, especially due to failure of selling the products. Although government has taken several steps to combat this situation, but the crisis is yet unsolved.