Role of Air Flow on Changing Soil Properties and Plant Nutrition in Egyptian Alluvial Soil

Study the effect of air flow on changing some soil properties and plant nutrition is highly important to increase crop quality and productivity. The pot experiment was carried out focusing on Agric faba bean C.V. Giza 2 in Egyptian alluvial soil (clay) during 2017-18 seasons. Two soil samples with three replicates were taken. The results revealed that hygroscopic water (HW), saturation percentage (SP) and real density (RD) have not affected by air flow, while organic matter (OM), hydraulic conductivity (HC) and bulk density (BD) have remarkable increase with air flow. The available macro and micronutrients concentrations in soil and plant are also discussed where different results have been obtained depending upon type of nutrient. The total count of bacteria (TCM) is found to be affected with air flow than without aeration techniques. The findings of this study reveal that aeration or air flow promotes healthy levels of soil gases and plays a critical role in plant growth.

Determination of the Hydrodynamic Parameters of Two Types of Soil in the Senegal River Delta. Simulation of Hydro-saline Transfers: Application to the Wind Deflation Phenomenon

In the Senegal River delta, the presence of a shallow salt water table associated with a strong evaporative demand sometimes leads to an upwelling of salts that crystallize on the surface. This phenomenon can be observed in the vicinity of the Diawling Basin, where a powdery structure sensitive to wind deflation and a massive structure with a fractionation into platelets that cannot be transported by the wind are noted. To understand the hydrodynamic characteristics of these soils, we used numerical simulation of water and solute transfers. The hydrodynamic parameters were determined in the laboratory using Wind's method on undisturbed samples. The experimental retention h() and hydraulic conductivity K(h) curves were fitted using the Van Genuchten model. The simulations show that the soil with a powdery structure has hydrodynamic characteristics that favour the ascent of salts from the water table to the surface. For the soil with a massive structure, the hydrodynamic conditions impose a deposition of salts in the subsurface.

Origin and Dynamics of Termite Mound Soils in Southern India

Aims: In Southern India, termite above-ground nests can have the shape of cathedral (CAT) or lenticular (LENT) mounds. Although CATare built by the fungus-growing species Odontotermes obesus, the origin and evolution of LENT remain unknown. Therefore, the aim of to study was to estimate the origin and dynamics of LENT from their specific physical and chemical properties. Study Site: This study was carried out in the Bandipur Tiger reserve (dry deciduous forest), Karnataka, Southern India. Methodology: All the soil samples were collected in a Fluvisol in the Mule Hole experimental watershed.Only large size mounds between 1.5 - 1.8m high were considered in this study. Soil samples were collected from the outer wall of CATnest and from the soil surface layer (0-5 cm deep) and surrounding soil. Particle-size distribution and dispersion were obtained by process of sedimentation. All the statistical analysis such as principal component analysis (PCA) were calculated using R studio and R version 3.2.1. Results: Using elemental physical and chemical properties, this study showed a gradient of soil properties from the soil sampled between 50-100 cm depth to CAT, LENT and the surrounding topsoil (CTRL, Fluvisol), suggesting that: (i) CAT can be considered patches in the landscapes with specific physical and chemical properties in comparison with CTRL and LENT; (ii) LENT mounds can result from the progressive modification of CTRL (autogenic origin of LENT) and their degradation leads to a progressive recovery of CTRL properties or (iii) they originate from the colonization of abandoned CAT by other termite species (exogenic origin of LENT). Conclusion: This study confirms the complexity of CAT and LENT fates and the need for long-term datasets to determine the origin and evolution of termite mounds.

Bio-availability and Bio-accessibility of Lead and Zinc in Contaminated Soil from Cwymystwyth Lead Mine Site

Cwmystwyth Lead Mine was an abundant mine site with pugh’s and kingside water drainages shows contaminated water in the research area with no much scientific evidence to ascertain the level of the pollution. Hence this research was designed to study level of lead and zinc in contaminated soil in which the bio-availability and bio-accessibility were measured. Sixteen (16) soil samples were taken at random using soil auger and a hand trowel. The samples were dried using an oven set at a constant temperature of 400oC for 72 hours. Wire mesh (250 microns) was used to sift the samples. The Unified (BARGE) method was used. The mimics mixtures of saliva, gastric, duodenal, and bile fluids. Three-stage mimic processes were performed, in the mouth, the stomach and intestinal cavities. All mimic digestive fluids were placed in the rotator water bath for 1hr at 37oC. The bioaccessibility of the soil Samples were analyzed by inductively coupled plasma-optical emission spectrophotometer (ICP-OES) method. The results were obtained using XRF and ICP methods. The percentage concentration of lead in the topsoil was 0.64% and in the bottom soil was 1.47%, with a total mean concentration of 1.06% in combined top and bottom soil. Zinc concentrations in the top and bottom soils were 0.22 and 0.45%, respectively, with a computed total mean of 0.34%. The findings revealed a highly significant difference between lead and zinc in both the top and bottom soil samples (LSD = P0.05). The average concentrations of lead and zinc extracted in both the stomach and intestinal stages were 15.98% and 1.23%, respectively

Phytoextraction of Lead: Its Feasibility, Constraints and Concerns

Aims: With lead being one of the most common soil contaminants and phytoextraction has been reported as a prospective method for remediation of lead-contaminated soil, this review aims to examine the feasibility of lead phytoextraction as well as its constraints and concerns. Study Design: This is a literature review. Methodology: Peer-reviewed papers were sourced from scholarly databases. The papers included in the review were mainly those about phytoextraction of lead, particularly with the shoot, soil and root concentrations of lead mentioned as well as the bioconcentration and translocation factors stated. Besides, papers discussing the limits, for instance, the duration of lead phytoextraction, and concerns of the approach were also included. Results: This review found only 11 plants have been reported to accumulate lead in shoots at nominal threshold of near or above 1,000 mg Pb/kg dry weight and in certain cases, soil amendment was required to achieve this. Only two of the plants had bioconcentration factor > 1 and another two had translocation factor > 1. None of the plants fulfilled all three criteria of a successful hyperaccumulator, indicating the constraints and a lack of feasibility of lead phytoextraction. Besides, lead phytoextraction has been predicted to require significant amount of time, hence increasing the risk of exposure to lead. Conclusion: This review highlights that lead phytoextraction may not be feasible for the remediation of lead-contaminated soil. It recommends phytostabilization as a more viable alternative to immobilize lead in rhizosphere and reduce lead exposure.

Contribution of Selected Herbivores’ Dung on the Soil Organic Carbon and Nitrogen in Serengeti National Park, Tanzania

This study was done to determine the contribution of selected herbivores’ dung in the grazed ecosystem of Serengeti National Park, Tanzania. To achieve this Soil Organic Carbon and Nitrogen were determined in four distinct textural soils in three sites, namely Serena with clay and clay loam, Barafu with sandy loam, sandy clay loam, and Seronera with sand clay loam. Thereafter the decomposition of dung pats in terms of weight change and percentage of nutrients in dung pats of four herbivore species (buffalo, zebra, wildebeest and elephant) incorporated into the soil beneath the dung pats were determined. Fresh dung, soil cores beneath the dung pats and control soils 1 m adjacent to the pats were taken for laboratory analysis. Dung pats and soil samples were analysed for initial percentage OC, N, pH and soil particle size distribution. Weight changes of the dung pats after each three weeks period were monitored. Similarly, monthly rainfalls during the study period were recorded from the rain gauges near the sites. The results indicate that the surface soil (0-15 cm depth) pH ranged from 6.0 - 7.5, 7.4 -7.9 and 6.1 - 7.4 for Serena, Barafu and Seronera respectively. While the soil texture was highly significantly different in percentage OC added after 18 weeks, the treatments and texture were both not significant for percentage N increased in the soil after 18 weeks. There was a difference of 1% between the ruminants and non-ruminants in percentage N increase although they were fluctuating over time due to weather changes. The C/N ratios of the controls and the treatments were on average 11 and 15 respectively, being highly significantly different and indicating that, treatments had a potential contribution to the soil OC and N in the ecosystem.

Freundlich and Langmuir Isotherm Studies of Phosphorus Sorption unto Soils Derived from Basement Complex Rock, Alluvium, Coastal Plain Sand and Shale Parent Materials

To provide information on best model to predict Phosphorus (P) Sorption unto Soils derived from Basement Complex Rock, Alluvium, Coastal Plain Sand and Imo Shale Parent Materials in 3 states of Nigeria. Completely randomized design was used to collect surface soil samples in 3 replications from 4 locations in Nigeria. Samples were collected from Idanre, Koko, NIFOR and Uhonmora in Ondo, Delta and Edo states Nigeria, laboratory analysis was carried out in the Central analytical laboratory of Nigerian Institute for Oil-Palm Research (NIFOR) Benin City, Nigeria between march 2016 and September 2017. Soil samples were equilibrated in 25 ml of 0.01 M CaCl2 containing various concentration of P as KH2PO4 to give 0, 50, 100, 150, 200 and 250 mg/L P for 24 hours (h) at room temperature 25 ± 2oC. 3 drops of CHCl3 was added to inhibit P mineralization. The suspension was shaken for 24 h on a reciprocating mechanical shaker, centrifuged at 7000 rpm After equilibration, decanted and P determined using spectrophotometer. The sorption data were fitted to linear Freundlich and Langmuir sorption isotherm. Considering the Freundlich model, P adsorption capacity (a) and P sorption energy (n) was highest in soils B (1400 mg kg-1) and (2.806 L kg-1) respectively. The Freundlich model fitted better to the data obtained with average root mean square error (RMSE) and R2 value of 0.69 and 0.951 respectively, as against average RMSE and R2 value of 1.60 and 0.883 respectively obtained from Langmuir model. The sorption data fitted well to Freundlich and Langmuir isotherms of which Freundlich Adsorption model was found to be better based on lowest RMSE (0.69) and highest regression (R2 = 0.951) value. Freundlich model should be adopted to determine P sorption characteristics of the soils studied. These predictors, however, need further works to validate reliability.

Effect of [N-(Phosphonomethl)-glycine] (Glyphosate) Herbicide on Soil Microbial Population

Aims: To determine the effect of [N-(phosphonomethl)-glycine] (glyphosate) herbicide on soil bacterial and fungal population. Study Design:The effect glyphosate herbicide on soil microorganisms population on 2 different farm land was determined by Isolation of bacteria and fungi from untreated and Glyphosate herbicide treated soils using Nutrient agar and Potatoes dextrose agar (PDA) for the bacteria and fungi respectively. The number of bacteria and fungi present in both treated and untreated soil was then enumerated and the isolates determined. Place and Duration of Study: The study is a cross sectional research and was conducted on two Farm lands located at Yola capital city of Adamawa state Nigeria wheresoil samples were collected and Microbiology laboratory of Modibbo Adama University Yola were the sample was processed and analyzed. The study was conducted from February to May of 2021. Methodology: Bacteria and fungi were isolated from soil samples before and after treatment of the soils with N-(phosphonomethl)-glycine(Glyphosate) herbicide at different concentration, the bacteria and fungi populations isolated both before and after the treatment were compared. Results: The study showed that Glyphosate herbicide caused reduction in the bacterial and fungal count from 3 days of treatment up to 15 days. The bacterial count reduced from 6.1x108cfu/g in the untreated soil to 1.6x108cfu/g on the treatment. Also the fungal count reduced from 1.0x108cfu/g in the untreated soil to 5.0x107cfu/g after 15days of soil treatment. Both the bacterial and fungal count continues to show a gradual decrease up to 15 days in the treated soil. However, several bacteria and fungi were isolated with Bacillus spp. and Micrococcus spp. having the bacteria with highest occurrence with 42(19.91%) and Aspergillusspp. as the fungi with the highest occurrence with 12(42.85%). Statistical analysis of the data obtained indicated that At 95% confidence level, there is a significant difference in the population of bacteria and fungi before and after the soil treatment P-value(T˃t)=.001 Conclusion: The study revealed that Glyphosate herbicide has a negative effect on soil bacteria and fungi population.

The Effect of Land Uses on Soil Erodibility (Index) and Soil Loss of the Keana Geological Sediments of Parts of Nasarawa State, Nigeria

The effect of land uses on soil erodibility and soil loss of the Keana geological sediments of parts of Nasarawa State, Nigeria was investigated in this study. Geographic positioning system (GPS) was used to identify three land uses (agricultural, forested, and residential). Soil samples were collected from top soils at 0-30 cm depth using core sampler from 1 ha of each land use in 8 settlement communities (16 locations). Standard laboratory methods for soil analysis were followed for determination of Dispersion ratio, Erosion ration, Clay ratio and Modified clay ratio. Linear regression and correlation were used to determine the logical relationship between the erodibility index and corresponding soil loss. The soils from the study area were classified as sandy loam and sandy clay loam with high density, high permeability and porosity making them less vulnerable to shear stress. Dispersion ration (DR) modified clay ratio (MCR), Clay ratio (CR) and Erosion ratio (ER) where high, which suggests that soils from the study area are vulnerable to erosion at various degree of susceptibility. Mean value of erodibility factor (K) and predicted soil loss of 0.0492, 0.0460 and 0.0357; 7.77, 7.20 and 5.48 tonnes/hectare/year for agricultural, forested, and residential lands respectively. The findings suggest that land uses influence the soil erodibility in the formation is in this order residential land > agricultural land > forested land use. The erosion class is ‘very low’ for forested (soils in this class have very slight to no erosion potential), ‘low’ (soil losses will occur) for agricultural and residential land uses respectively. These findings suggest that soil erodibility has been significantly influence by land use change in Keana geological sediment.

Vegetative Growth and Ion Relations in Soybean with Potassium Sulphate Application under Saline Environment

Aims: To evaluate the effect of K2SO42- application on growth of soybean cultivars besides chemical parameters under salt stress. Study Design: Laid out the experiment in Complete Randomized Design in triplicates. Analyzed the data statistically by using the statistical software Statistix 8.1. Place and Duration of Study: The study was conducted in Soil Salinity and Bio-saline Research green house and in the laboratory of Land Resources Research Institute at National Agricultural Research Centre, Islamabad (under PARC), Pakistan for three months. Methodology: To study germination parameters under salt stress, NaCl was used @ 0, 100, 120 and 140 mmol L-1. At seedling stage, interactive effect among salt stress (0 and 4.5 dSm-1), potassium sulphate (KS) application @ 10 mmol L-1 and soybean (Cvs. NIBGE-301 and NIGBE-158) was recorded for growth and ion relations. Results: Germination, biomass, bio vigor, mass vigor and sap vigor of the seedlings and ion relations were affected highly significantly (p≤ 0.01). Under interactive effect of KS and salt stress at vegetative stage, Na+/K+ in the plants declined with KS application. Sulphur and phosphorus concentration in the plants changed under the same conditions. Conclusion: Induced salt stress revealed germination, seed bio vigor, seeding mass vigor, and seedling sap vigor seedling and other vegetative parameters of soybean cultivars. Potassium sulphate application revealed genotypes differential response to ion relations and growth under salt stress. NIBGE-301 was more tolerant to salt stress and more responsive to potassium sulphate application than NIGBE-158.