Calcareous Sandy Research Articles

The sedimentology and sequence stratigraphy of contourites and associated rocks at the northeastern passive margin of Gondwana during the Early Triassic (Induan - Mirga Mir Formation), Iraqi Kurdistan

Contourite deposits are recognized for the first time from the Lower Triassic Mirga Mir Formation in the Kurdistan region, Northern Iraq. The formation represents deposition on the southern passive margin of the Neo-Tethys during its early opening stages. The contourites are characterized by lenticular and sorted siltstones to fine-grained sandstones with current ripples, cross beddings and scour surfaces. These current structures are associated with thin-bedded (5–20 cm) limestones and shales. Petrographic investigations of the associated carbonate successions show both skeletal and non-skeletal grains such as peloids, ooids, intraclasts and extraclasts. Deposition occurred in a ramp setting at the southern passive margin of the Neo-Tethys and the skeletal grains reveal deep open marine and shallow warm water. Four different facies associations are recognized: Offshoal/basinal, foreshoal/slope, shoal and back shoal/lagoon. Field observations and thin section analysis revealed four main contourite facies in the studied outcrops, namely muddy contourites, silty contourites, sandy contourites and calcareous sandy contourites. The contourites are integrated with the basinal, offshoal, foreshoal and slope deposits. Stable isotope data from the carbonates of Mirga Mir Formation show that the δ18O (‰) values are negatives but the δ13C data shows negative and positive values. They show that had underwent meteoric diagenesis and that the δ13C values still preserving their primary depositional signal. The carbon isotopes data conforms to available data from the surrounding countries and by comparison with Early Triassic δ13C stratigraphic trends, it had captured at least two of the well-known positive spikes and at least one of the negative dips. Sequence stratigraphic analysis and stacking patterns revealed that the Mirga Mir Formation can be divided into two third-order depositional sequences. Each sequence is characterized by TST deposits followed by HST deposits and without LST.

Significance of Some Soil Amendments to Improve Plant Growth and Nutrients Uptake in Some Soils

Many problems facing sandy, calcareous and heavy clay soils and restricts plant growth, nutrients availability and sustainable agriculture. Soil amendments are considered to be the most realistic soil management methods to improve soil chemical and physical properties. Improving some soil physical and chemical properties, study the correlation between soil properties and their effect on plant growth and nutrients uptake by faba bean plant (Vicia faba L. var.716) were the main purpose of this study. To achieve this purpose three factorial pot experiments were conducted by addition rates (0, 5 and10 ton. fed-1 ) of farmyard manure (FYM), phosphate rock (PhR) and rice straw (RS) either alone or mixed to sandy, calcareous sandy loam and clay soils. Soils were incubated with the studied treatments for 15 days before planting. The main results showed that the addition rates of soil amendments led to slightly increase in soil salinity, total porosity and significant increase in organic matter content in the experimental soils. Bulk density and pH decreased with increased the rates of FYM and PhR either alone or mixed with RS. Decreasing in hydraulic conductivity in sandy and sandy loam soils, while it increases in clay soil. Generally, there are negative correlations between soil organic matter and both of hydraulic conductivity and bulk density in sandy and sandy loam soils, while, organic matter and hydraulic conductivity gave a positive effect in clay soil. Changes in soil properties had a positive effect of faba bean growth and macro nutrients uptake. The highest rates of the studied materials showed a significant increase in fresh and dry weight, NPK content and uptake of faba bean plant. Integrated use of the highest rates of FYM and PhR with RS were the best option for sustaining physical and chemical properties, enhancing faba bean growth and nutrients uptake of the studied soils.

The aging effects of biochar and Zn2+ on adsorption and desorption kinetics of Pb2+ in a calcareous sandy soil

ABSTRACT Adsorption and desorption rates play an important role in the availability and mobility of Lead (Pb2+) in soils treated with biochar. However, information is still limited about the effects of pyrolysis temperature, presence of Zn and incubation times on these processes. This study was performed to investigate the effects of 1% (w/w) walnut leaves biochars produced at different temperatures (200 °C (B200), 400 °C (B400) and 600 °C (B600)) on adsorption and desorption kinetics of Pb2+ in the presence of Zn2+ at two incubation times (30 and 90 d). Results explained that the adsorption rate of Pb2+ was decreased with increasing the pyrolysis temperature, whereas the desorption rate of Pb2+ was increased. In the presence of Zn2+, there was a decrease in the adsorption sites for Pb2+, while there was an increase in the available desorption sites for Pb2+. The rate of Pb2+ adsorption in 90 d of incubation was higher than 30 d of incubation, whereas the rate of Pb2+ desorption in 90 d of incubation was slower than 30 d of incubation. It can be concluded that 1% (w/w) walnut leaves biochar could not immobilize Pb2+ in the soil because more than 74% adsorbed Pb2+ desorbed in DTPA-TEA solution.

Long-term effects of grain husk and paper fibre sludge biochar on acidic and calcareous sandy soils – A scale-up field experiment applying a complex monitoring toolkit

Biochar is produced from a wide range of organic materials by pyrolysis, specifically for improvement of poor quality soils. One of the main issues nowadays in studying biochar as soil amendment is to upscale experiments and move from short-term, laboratory conditions to long-term field trials.This paper presents a long-term field study, being the final step of a scale-up technology development, on grain husk and paper fibre sludge biochar application for soil improvement with focus on two degraded soil types of a temperate region. The effects of biochar on an acidic and a calcareous sandy agricultural soil were studied applying a complex approach including physico-chemical, biological and ecotoxicological methods. Our study demonstrated that the applied biochar had positive direct and indirect influences on the acidic sandy soil, but these effects were different in terms of extent and time. 30 t/ha biochar addition improved the pH of the acidic sandy soil by 24% and also increased significantly the nutrient concentrations (P2O5 by 68%, K2O by 11% and organic matter by 33%), and the water-holding capacity after 30 months. Furthermore, biochar addition improved also the microbiological activity and diversity in the acidic sandy soil. Biochar application did not induce any negative effects. Biochar had no toxic effect on the plants and the biochar-treated soil provided a more liveable habitat for soil living animals than the untreated acidic sandy soil.The favourable biochar-mediated influences on soil properties were manifested mainly in the acidic sandy soil, proving that the biochar-related advantages have to be verified for different soil types. The benefits of grain husk and paper fibre sludge biochar application in an acidic sandy soil were confirmed on the long term by the applied tiered approach.

Influence of nutrient management and establishment methods on yield and economics of rice in calcareous soils of Bihar

The present investigation was carried out at Research Farm, Dr. Rajendra Prasad Central Agricultural University Pusa, Bihar during kharif 2018 on calcareous sandy loam soil. The experiment was laid-out in a split-plot design (SPD). The main-plot treatments included three crop establishment methods, viz. puddled transplanted rice (M1-TPR), wet direct-seeded rice (M2-DSR-wet) and dry direct-seeded rice (M3-DSR-dry). In sub-plots, five different nutrient management methods were T1 (100% STCR Based Dose of Fertilizer + ZnSO4 @ 25 kg ha-1), T2 (75% DF + 25% STCR based Recommended Dose of Nitrogen through Vermicompost), T3 (100% STCR based Recommended Dose of Nitrogen through Vermicompost), T4 (100% DF + 50% STCR based Recommended Dose of Nitrogen through Vermicompost) and T5 (50% DF + 25% STCR based Recommended Dose of Nitrogen through Vermicompost) were replicated thrice under each method. The results found that the plant height, yield attributing characters(number of tillers per meter square, number of panicles per meter square, filled grains per panicles and test weight) and yield recorded significantly higher values under transplanted rice with T4 (100% DF + 50% STCR based Recommended Dose of Nitrogen through Vermicompost) recording significantly higher values among different nutrient management systems. The economics of all the cultivation practices recorded higher B:C ratio (0.73) and net returns (₹ 34684 ha-1) under DSR-wet with T1 (100% STCR Based Dose of Fertilizer + ZnSO4 @ 25 kg ha-1) giving farmers an alternative method for rice production.

Biofortification of green bean (Phaseolus vulgaris L.) and lettuce (Lactuca sativa L.) with iodine in a plant-calcareous sandy soil system irrigated with water containing KI

Uptake and translocation of iodine by green bean (Phaseolus vulgaris L.) and lettuce (Lactuca sativa L.) were investigated in a calcareous sandy soil-plant system. These plants were cultivated in calcareous sandy soil in presence of irrigation water with the iodine concentrations of 0.10, 0.25 and 0.50 mg/L. The growth of these plants was stimulated at the two lower iodine concentrations of 0.10 and 0.25 mg/L, but hampered at 0.50 mg/L. In lettuce the highest iodine dosage resulted in smaller leaf surface and higher number of leaves, nearly with the same biomass production. In the edible parts of green bean and lettuce plants irrigated with 0.25 mg/L iodine containing water, the iodine concentration levels amounted to 0.6 and 5.2 mg/kg dry weight (DW), respectively. In lettuce, the uptake and translocation of selected essential elements (P, Mg, Mn, Fe, Cu, Zn, B) were also stimulated (20-260%) by iodine treatment; however, in fresh bean pods this phenomenon was negligible. Considering the iodine level and moisture content of the fresh lettuce leaves and fresh bean pods, the consumption of 100 g fresh vegetable covers about 66%, 3% of the recommended dietary allowance (150 μg).

Inocybe woglindeana, a new species of the genus Inocybe, thriving in exposed habitats with calcareous sandy soil

Inocybe woglindeana, a new species of the genus Inocybe, thriving in exposed habitats with calcareous sandy soil

Development the Wide Ridges Machine for Laying Drip Irrigation Tubes and Plastic Mulch in Ras Sudr-South of Sinai

Mulching facilitates more retention of soil moisture and helps in control of temperature fluctuations, improves physical, chemical and biological properties of soil. As, it adds nutrients to the soil and ultimately enhances the growth and yield of crops. The desired outcomes from raised-bed (wide ridge) are to: drain, aerate, prevent water logging, increase root growth, thereby reinforce the loose structure, increase soil organic matter, increase plant water use, reduce deep drainage and increase production. Therefore, a mulching machine was designed and manufactured to suit different dimensions of chilli raised-beds in Egypt in agriculture. The traditional machine using to build the wide ridges (raised-beds) was developed to suitable for installing raised-bed, cover it with plastic films and laying the drip irrigation pipes (surface and subsurface) at the same time. The developed part consists of main frame, plastic roll carrier unit, drip irrigation pipes roll carrier unit, press wheel assembly, soil covering unit, bed former and three hitching points. The developed machine has overall dimensions 2600 x 2000 x 1250 mm (L x W x H). The weight of the developed plastic mulch-laying machine is 322 kg (without plastic mulch roll and drip pipes roll). The total fabrication cost of the mulch machine was 20000 LE with 2019 price level. The developed machine was evaluated in Ras-Sudr research station, south Sinai governorate on calcareous sandy loam soil at three different speeds of operation (2, 3 and 4 km/h), two different methods to use plastic mulch (with and without) and two different methods to lay the drip irrigation pipes (surface and subsurface). The effect of study treatments on actual field capacity, field efficiency, pulling force, fuel consumption rate, total water stored, water consumptive use, water application efficiency, width and thickness of soil cover, width and height of raised-bed, mulching efficiency, chilli yield, productivity of irrigation water, soil salinity, cost of developed machine and cost for manual process were studied. From this study, it was concluded that using developed machine for installing raised-bed and laying both plastic mulch and drip irrigation pipes (surface and subsurface) at the same time. Led to a 68% decrease in costs compared to the manual method of using the machine before development to install the raised-bed, then laying both plastic mulch and drip irrigation pipes (surface and subsurface) manually. The results of evaluation experiment for the developed machine showed that although at low speed 2 km/h, the actual field capacity decreased and costs increased by an average of 44% and 62%, respectively, compared to the speed of 4 km/h. However, at a speed of 2 km/h, the pulling force, fuel consumption rate and soil salinity decreased about 14%, 15% and 14% respectively and field efficiency, total water stored, water consumptive use, water application efficiency, chilli yield and productivity of irrigation water about 4%, 6%, 4%, 16% and 15% respectively compared to the speed of 4 km/h. The results also showed that at a speed of 2 km/h, the width and thickness of the soil cover of the plastic edges increased about 74% and 98%, respectively, and the width and height of the raised-bed increased about 23% and 20%, respectively, compared to the speed of 4 km/h. The highest mulching efficiency 97% was achieved at a speed of 2 km/h and when laying drip irrigation pipes sub-surface compared to 66% at speed of 4 km/h and laying drip irrigation pipes on soil surface. Therefore, the study recommends using the developed machine to install a raised-bed and laying both of plastic mulch on its surface and drip irrigation pipes sub-surface at a speed of 2 km/h achieved the highest efficiency in implementing this system at the lowest cost. Also, worked to increase the irrigation use efficiency, reduced soil salinity and increased yield of chilli crop.

Effect of household waste based vermicompost and fertilizer on phosphorus and potassium mineralization in calcareous soil of Bihar

An incubation experiment was conducted during Kharif 2018 at RPCAU, Pusa to examine the mineralization of vermicompost in calcareous sandy loam soil at five different stages which match with the critical growth stages of rice crop and the experiment was conducted in Completely Randomized design (3 factors) replicated thrice. There were four levels of vermicompost along with three levels of chemical fertilizers used at field capacity (19.47%) in combinations and alone. Results indicated that content of available P2O5 and K2O in soil increased up to 65 DAI then decreased gradually. Application of increasing level of vermicompost and fertilizer alone or in combination resulted in corresponding increase in the available nutrient content of soil. During the study, it was observed that the treatment combination involving application of highest dose of vermicompost (3.75 t ha-1) along with full dose of fertilizer (RDF) was significantly superior.

Optimization of Lignite Particle Size for Stabilization of Trivalent Chromium in Soils

ABSTRACTStabilization capacity of 5% by weight lignite added in three particle size ranges (<0.5; 0.5–1.0 and 1.0–2.0 mm) to acidic (pH = 5.0) or calcareous (pH = 7.7) sandy soil samples of <2 mm grain size artificially contaminated with 375 mg/kg Cr(III) was assessed through fit-for-purpose leaching tests performed with CH3COOH, NH2OH·HCl and EDTA. About 90% and 60% of Cr(III) were immobilized in calcareous and acidic soils per se, respectively. Although the point of zero charge measurements (pHpZC≈4.5) indicated that lignite could effectively bind positively charged Cr hydroxo complexes at the pH of the calcareous soil, the application of lignite is unnecessary due to the low solubility of these species. Although the acidic soil mobilizes Cr, the addition of lignite has been proven to stabilize it. The phytoavailable Cr fraction in the soils per se was about 10–25%. In spite of the mobilization of Cr by acidic soil, the phytoavailable Cr concentration decreased to about half when the lignite particle size was either 0.5–1.0 or 1.0–2.0 mm. Lignite was suitable for Cr stabilization in acidic soil in a close particle size range, ensuring the dispersibility needed to enhance efficient Cr transfer from the contaminated soil to the stabilizer.

Effect of biochar application on barley plants grown on calcareous sandy soils irrigated by saline water

In sustainable agriculture, protect the ecosystem by reducing chemical fertilizers are the main goal. Applying biochar to soils is a method to increase the available nutrients, improve soil physio-chemical characteristics and enhance plant growth. The current experiment assess, the influences of biochar (BC) on barely growth under saline conditions. Barely plants grown on a calcareous sandy soil were amended with BC at a rate of 0 (CK), 1 (BC1) and 3% (BC3) of soil weight and irrigated by saline water ( EC=13.8 dS m−1). The results showed that BC treatments realized significant effects on soil salinity, pH, soil organic matter (SOM), and plant nutrients. The diverse dosages of biochar of BC1 and BC3 could enhance SOM by 42.4 and 55.2% and the dry biomass was ameliorate by 4.7 and 15.4 %, respectively compared to the control. The biochar additions to soil increase the agronomic parameters preformance of nutrients utilization by barley plants. The results confirmed that the added biochar could augment the barley production, and improve the soil characteristics under saline conditions as well as its contribution for agriculture sustainability.

Effect of irrigation water containing arsenic on elemental composition of bean and lettuce plants cultivated in calcareous sandy soil

BackgroundThe uptake of arsenic by vegetables from soil irrigated with arsenic enriched groundwater poses a major health hazard. The edible portion of these vegetables transfer arsenic to the human beings. The uptake of arsenic was studied in bean (Phaseolus vulgaris L.) and lettuce (Lactuca sativa L.) in a controlled greenhouse pot culture with calcareous sandy soil as substrate. The plants were irrigated with water containing sodium arsenate at concentrations 0.1, 0.25 and 0.5 mg L− 1. The total arsenic concentration of the different plants parts was determined by ICP-MS, following microwave-assisted acid digestion. The change in plant biomass production and essential macroelements (Mg, P, K) and microelements concentration (Fe, Mn, Cu, Zn) was also studied.ResultsThe As concentration in the bean was in the order: root>stem>leaf>bean fruit and in lettuce: root>leaves. At the highest dose (0.5 mg L− 1) the As concentration in the bean fruit and lettuce leaves was 22.1 μg kg− 1 and 1207.5 μg kg− 1 DW, respectively. Increasing As concentration in the irrigation water resulted in decreased edible biomass production in bean, while in lettuce the edible biomass production increased. Neither plant exhibited any visible toxicity symptoms. No significant change was observed in the macro and microelements concentration. The total and the water-soluble arsenic in soil amounted to 3.5 mg kg− 1 and 0.023 mg kg− 1, respectively. The transfer factor was found to increase with increase in the As treatment applied. The transfer factor range for bean from root to fruit was 0.003–0.005, and for lettuce from root to leaves was 0.14–0.24.ConclusionConsidering the FAO-WHO recommended maximum tolerable daily intake (MTDI) limit of 2.1 μg kg− 1 body weight, and the biomass production, both plants should not be cultivated at As treatment level higher than 0.1 mg L− 1.Graphical abstract

Nehézfém- és egyéb toxikus mikroelem-terhelés tartamhatása a talajból mért visszanyerési százalékuk alakulására szabadföldi kísérletekben

Összefoglalás Dolgozatunkban Kádár Imre 1991 tavaszán meszes csernozjom talajon 13 potenciálisan toxikus mikro- / károselem (Al, As, Ba, Cd, Cr, Cu, Hg, Mo, Ni, Pb, Se, Sr és Zn) 0-90-270-810 kg ha−1 szintjeivel beállított szabadföldi tartamkísérlete 1-20. évi talajvizsgálati-, illetve talaj visszanyerési százalék eredményeit értékeltük. A LE-oldható (NH4-acetát+EDTA) és „összes” (cc.HNO3+cc.H2O2) elemtartalmak aboszlút értékeinek változásai mellett figyelemmel kísértük az elemek visszanyerési százalékainak időbeni változásait is. A kísérlet 4. évében a legnagyobb talaj LE-oldható visszanyerési százalékokat a kationos formában kiadott elemek esetében kaptunk, míg az anionos formában kijuttatottak (Se, As, Mo, Cr) az elemsorrend második felében, illetve a végén helyezkedtek el. A kísérlet 18. évére a legtöbb elem LE módszer szerint kimutatott oldhatósága, és így visszanyerési százaléka kisebb-nagyobb mértékben csökkent. Legnagyobb csökkenéseket a Sr, Pb, Zn, míg legkisebbeket a Mo, Cr és Cd elemek mutattak. A tápláléklánc szennyeződése szempontjából kedvezőtlen, hogy a kijuttatott karcinogén Cd jelentős hányada maradt a könnyen oldható frakcióban, és ez a frakció a 14 év alatt is csak minimálisan csökkent a meszes csernozjom talajon. Az elemek átlagában, a LE-oldható elemtartalomban mért visszanyerési százalék 1994-ben 41%, míg 2008-ban 22% volt. A 14 év alatt tehát az átlagos, LE-oldható elemtartalomban mért visszanyerési százalék 19 abszolút %-kal csökkent, azaz gyakorlatilag megfeleződött. Az egyes elemek „összes” elemtartalomban a kísérlet 4. évében mért visszanyerési százalékának sorrendje a LE-oldható tartalmaknál leírtakhoz hasonlóan alakult; a legkisebb visszanyerési százalékokat itt is az anionos formában kijuttatott elemeknél kaptunk. Míg a LE-oldható tartalmaknál a Hg, addig az „összes” elemtartalmaknál a Cd, mint nehézfém ékelődött be az anion formában kijuttatott elemek közé. A kísérlet 18. évében az „összes” elemtartalomban mért visszanyerési százalékok esetében a legnagyobb csökkenéseket a Se, Sr, Pb, míg legkisebbeket a Cd, Mo és Cr elemek mutattak. Az utóbbi három elem közül humán egészségügyi szempontból a Cd tekinthető a legveszélyesebbnek. Az elemek átlagában, az „összes” elemtartalomban mért visszanyerési százalék 1994-ben 81%, míg 2008-ban 49% volt. A 14 év alatt tehát az átlagos összes elemtartalomban mért visszanyerési százalék 32 abszolút %-kal Csökkent. A meszes csernozjom, meszes homok, és savanyú, agyagos vályog textúrájú barna erdőtalajon beállított károselem-terheléses tartamkísérlet adatainak tanúsága szerint a LE-oldható elemtartalomban kifejezett, és az „összes” elemtartalomban kifejezett visszanyerési százalékok egymáshoz viszonyított aránya inkább elem-, mint talajtulajdonság-függő. Úgy találtuk, hogy a három, egymástól jelentősen eltérő tulajdonságú talajon viszonylag azonos időben, azonos mennyiségben és azonos formában kijuttatott potenciálisan káros elemeknek a LE-oldható elemtartalomban mért visszanyerési százalékok és ”összes” (cc.HNO3+cc.H2O2-oldható) elemtartalomban mért visszanyerési százalékok arányainak sorrendje állandó, tehát a talajtulajdonságoktól független volt. Ezen felismerés alapján fogalmaztuk meg a Szabó-Csathó-Kádár-féle potenciálisan toxikus talaj-mikroelem kiterjeszthetőségi szekvens megnevezést. Természetesen ezen hipotézisünket még számos más talajtípuson, hasonló feltételekkel beállított tartamkísérletben is szükséges lenne bizonyítani.

Bagasse Pith-Vinasse Biochar Effects on Carbon Emission and Nutrient Release in Calcareous Sandy Soil

Local waste recycling has many benefits to environmental, economic, social, and health aspects. Arid regions, especially calcareous sandy soil, where high rates of organic matter decomposition led carbon emission to increase, are poor in their content of organic matter and some nutrients as well as high phosphorus fixation in this soil. The objectives of this study were investigating effects of bagasse pith-vinasse biochar and incubation periods on: carbon (C) sequestration, carbon mineralization, and nutrients availability of calcareous sandy soil. The incubation experiment included four treatments: (1) unamended soil (control), (2) soil amended with 3% (w/w) bagasse pith-vinasse (BPV), (3) soil amended with 3% (w/w) biochar of bagasse pith-vinasse (BPVB), and (4) soil amended with 3% (w/w) BPV + BPVB (1:1) and incubated at 3, 7, 21 and 46 days. The results of this study revealed a decline in carbon emission with adding BPVB compared to BPV and BPV + BPVB this in turn leads to enhancing carbon sequestration. Available phosphorus improved significantly with adding bagasse pith-vinasse biochar compared with unamended soil. Phosphorus availability increases with increasing incubating durations for bagasse pith-vinasse biochar. At the end of the incubation, the phosphorus availability increased from 20.08 mg kg−1 soil for control to 20.36, 35.25, and 20.63 mg kg−1 soil for BPV, BPVB and BPV + BPVB, respectively. Moreover, potassium availability showed a significant improvement with BPVB application compared with unamended soil. We recommend adding biochar to low fertility soil because it plays an important role in the environmental management via improving soil fertility, local waste management, and climate change mitigation.

Performance evaluation of a MICP-treated calcareous sandy foundation using shake table tests

Calcareous sandy foundations are susceptible to liquefaction when subjected to dynamic loading such as seismic or wave loading, which could cause severe damage to the superstructure and incur significant financial losses. Therefore, reducing the liquefaction potential of calcareous sand is of considerable significance. Microbially induced calcite precipitation (MICP) treatment is a relatively new method to improve the liquefaction resistance of calcareous sand, and it has the advantages of incurring small disturbances, low grouting pressure, less environmental harm, long transmission distance and a remarkable effect pertaining to the improvement of the engineering properties of the soil. However, few studies have evaluated the application of MICP treatment to calcareous sandy foundations. In this study, several shake table tests were conducted to evaluate the seismic performance of MICP-treated calcareous sandy foundations. Special attention was paid to the shear wave velocities, natural frequency and shear strength of the calcareous sand during MICP treatment. Additionally, the horizontal accelerations, pore water pressures and vertical settlements of calcareous sand before and after the treatment were compared. After MICP treatment, the shear wave velocity, natural frequency and shear strength of soil were improved, which indicated that the strength and stiffness of the model were considerably improved. During the shaking, the excess pore pressure ratio and surface settlement of MICP-treated model were significantly decreased. The liquefaction resistance of the MICP-treated model demonstrated greatly improved. However, the surface accelerations of the model strengthened by MICP were amplified. The test results indicate that use of the MICP method can significantly improve the strength, stiffness and liquefaction resistance of calcareous sand.

Copper induced iron deficiency in wheat (Triticum aestivum L)

A pot experiment was conducted to study the interaction effects of phosphorus and copper on wheat. The soils used were calcareous loamy sand (ls) and non calcareous sandy loam (sl). Four levels of Cu (0, 5, 10 and 20 mg Cu kg−1 soil) and six levels of P (0, 25, 50, 100, 200 and 400 mg P kg−1 soil) were applied in all possible combinations with three replications. Soil pH decreased with Cu application while Olsen P increased with P application in both soils. Growth and yield of wheat improved significantly with graded levels of applied P. However, when any level of P was combined with 20 mg Cu kg−1 soil, severe iron chlorosis of leaves, a drastic reduction in growth and chlorophyll content was observed in calcareous ls only. The results indicated that it was Cu and not P that induced Fe deficiency in wheat grown in alkaline calcareous soil and the Cu requirement of the crop seemed to be much lower in the calcareous ls. Root dry matter, grain and straw yield decreased with increasing levels of applied Cu in ls but in sl maximum increase of 62.5, 74.3 and 63.7 per cent in root, grain and straw yield was observed with a combined application of 400 mg P and 5 mg Cu kg−1 soil over control. Accumulation of Cu in roots decreased the Fe absorption by roots which indicated that Fe chlorosis of wheat leaves is expected when Cu: Fe concentration ratio in root is > 0.30.

Improvement in phosphorus nutrition of wheat plants grown in a calcareous sandy soil by incorporating chemical phosphorus fertilizer with some selected organic substances

Established fertilizer recommendations for wheat is urgently required to enhance the application efficiency of commercial phosphorus (P) fertilizers. This study evaluated the effect of inorganic P combined with some organic supplements i.e., citric acid (CA) or pigeon manure juice (PMJ), on alkaline-calcareous soil as well as plant measurements and phosphorus efficiency parameters of wheat (Triticum durum ’Boussalem’). Different concentrations of P in solution i.e., 0.05, 0.10, 0.15, 0.20, and 0.40 mg l−1, were worked out theoretically using the Freundlich model. A greenhouse study was conducted on a permanent layout with three replicates. As a result, phosphorus in the control was 0.493 mg P pot−1. However, in amended pots with organic substances, the averages of P uptake were 0.701 and 0.785 mg P pot−1, respectively for PMJ and CA treatments. A lower P requirement of 0.195 and 0.245 mg P l−1 may be required in CA and PMJ treatments, compared to the control treatments (0.345 mg P l−1). In addition, the phosphorus absorption efficiency (PAE) was higher in the CA and PMJ treatments. So, it is recommended to apply P fertilizers with poultry manure juice as an alternative solution in order to improve the efficiency of inorganic P fertilizers and consequently reduce their application rates in alkaline calcareous soils.

A short-term effect of date palm biochars on NH3 volatilization and N transformation in calcareous sandy loam soil

A short-term incubation experiment (30-day) was conducted using a calcareous sandy loam soil (having pH of 7.65 and CaCO3 of 16.8) amended with urea (U) at application rate of 360 kg N ha−1 in the presence and absence of biochars (BCs) produced from date palm waste at two pyrolysis temperatures of 300 (BC300) and 500 °C (BC500) with application rate of (0 and 45 Mg ha−1) at different incubation temperatures of 15, 25, and 35 °C to investigate their short-term effects on soil ammonia (NH3-N) volatilization and different forms of nitrogen (N) transformation. The results showed that applying BC300 had 23.1% and 12.5% and 10.2% significant (P = 0.05) lower cumulative NH3-N volatilization than U treatment at incubation temperatures of 15, 25, and 35 °C, respectively. Meanwhile, applying high pyrolysis temperature BC (BC500) showed significant (P = 0.05) lower cumulative NH3-N volatilization only at 15 °C, which accounted for 21.9% lower than U treatment. The concentrations of ammonium (NH4-N) in the soil increased with the progress of incubation time and reached the maximum peak at days 3–15 of incubation. With the progress of incubation time, BC300-treated soil showed a higher concentration of NH4-N and ammonification rate than those of other treatments (U and U + BC500); however, BCs did not show significant effects on NO3-N concentration and nitrification rate. Hence, integrated use of urea and biochar pyrolyzed at 300 °C having acidic functional groups and high content of total acidity may serve as an efficient fertilization strategy for minimizing NH3-N volatilization and enhancing the available form of N in calcareous soils from an arid environment.

Promising Leuce poplar clones in sandy ridges between the rivers Danube and Tisza in Hungary: a case study

An intensive integrated research and development work has been carried out on the improvement of Leuce poplars including primarily the native white poplar (Populus alba L.) and its natural hybrid grey poplar (Populus × canescens). More than 70 percent of the Leuce poplar stands can be found on calcareous sandy sites in the Danube–Tisza region, so they play a significant role in the poplar management of this part of the country. The most important task ahead of Hungarian poplar growers is to improve the quality of poplar stands and plantations based on selecting new clones and cultivars. The growth and yield of four promising Leuce poplar clones was evaluated on a marginal site in central Hungary. The clones ‘H 425-4’ (Populus alba L. × Populus alba L.), and ‘H 758’ (Populus alba L. Mosonmagyaróvár 124) seem to be suitable for wood production, while the ‘H 427-3’ (Populus alba L. × Populus alba L. cv. Bolleana) and ‘H 422-9’ (Populus alba L. × Populus grandidentata (Michx)) clones (with decorative stem form) could be better used for tree lines and ornamental plantations.

Effect of inoculation with phosphate solubilizing actinomycete isolates on phosphorous uptake and growth of wheat grown in calcareous sandy soil

Two pot experiments were conducted in this study during the period of 2015 to 2017. The first pot experiment was conducted, during the winter, of 2015/2016 to test the effect of inoculation with nine actinomycete isolates on phosphorous uptake and growth of wheat (Triticum Sativa) plants in sandy calcareous soil and choose the best of two actinomycete isolates.