Medium Sand Research Articles

Statistical Evaluation of Sleeve Friction to Cone Resistance Ratio in Coarse-Grained Soils

The investigation of soil is a particularly important stage of structural design. Cone penetration tests (CPTs) are the most common soil investigation techniques. The results of these tests provide information about the values of cone resistance (qc) and sleeve friction (fs), which correspond to depth. Previous studies have shown that the ratio of sleeve friction to cone resistance depends on the particle size distribution in soil and its use for soil classification. Unfortunately, as an analysis of the literature shows, there is no such classification for coarse-grained soils. This paper presents statistically significant differences in the ratio of fs to qc in coarse-grained soils. Based on the research performed, the proposed coefficients depend on the classification of coarse-grained soils with respect to the size of the soil particles. The data investigated were obtained from study reports on 35 sites (5934 tests) at which the main type of soil was coarse-grained and contained different sizes of particles. Following a statistical analysis, five groups of tested coarse-grained soils, silty fine sand, clayey fine sand, fine sand, medium sand and gravelly coarse sand together with gravel, are derived. The analysed data show statistically significant differences in the ratio of fs to qc considering this particular type of soil. A ratio of fs to qc with a probability of 95% is proposed for sandy soils. The values for silty fine sand, clayey fine sand, fine sand, medium sand and gravelly coarse sand mixed with gravel are 0.009459, 0.010982, 0.009268, 0.008001 and 0.006741, respectively. A linear relationship between the fs and qc indexes is also suggested.

ANALISIS PENYELIDIKAN KARAKTERISTIK TANAH KOTA DENPASAR MENGGUNAKAN METODE BOR TANGAN, DAN UJI LABORATORIUM

ANALISIS PENYELIDIKAN KARAKTERISTIK TANAH KOTA DENPASAR MENGGUNAKAN METODE BOR TANGAN, DAN UJI LABORATORIUM

Impact of temporal beach grain size variability on aeolian sediment transport and topographic evolution in a microtidal environment

While the impact of the spatio/temporal variability of grain size on morphological beach state is reasonably well understood, relatively little is known on its impact at a scale of days/months on aeolian sediment transport. This study focuses on five short intensive wind events during which aeolian sediment transport measurements, beach surface sampling and elevation change surveys were carried out for 1 to 3 days, over a 16-month period on a microtidal beach dominated by offshore winds. Monthly observations show a high temporal variability in beach grain size in relation to the decoupling between hydrodynamic and aeolian processes, from medium sand after a marine storm and inundation of the beach, to very coarse sand after several weeks of storm-force winds. During each wind event, topographic change on the beach ranged from zero, to 0.55 m. The time scale of coarsening depended on the initial beach grain size and could be very fast when the beach was composed of medium sand (e.g. 388 μm sand changed to coarse sand of 547 μm in 40 h). In contrast, it took one month to transition from a coarse median beach grain size of 883 μm to a very coarse one of 1323 μm. This variability in grain size results in dramatically different rates of sediment flux. For example, during average wind speeds of 10 to 14 m/s the sediment flux when the beach was composed of medium sized sand ranged between 21 and 154 kg/m/h compared to 0.4 to 50 kg/m/h when the beach was composed of coarse and very coarse sized grains. Overall, this study highlights the importance of beach grain size variability on aeolian sediment transport and shows that for similar incident wind and climatic conditions aeolian sediment transport rates vary dramatically. The study demonstrates the importance of taking care when using a constant median grain size in the calculation of long-term aeolian sand transport on beaches with heterogeneous spatial and temporal beach grain size variability.

Correlation between volume weight, porosity and moisture content in Central Kalimantan’s Peatlands

Peat is determined by soil characteristics consisting of maturity, color, low PD, low BD, texture, and organic content, which are different from mineral soil types, which can store more water with relatively high porosity, can decrease if drought due to lack of peat wetting with fiber spaces blackish brown with a fine structure. The purpose of this study was to determine the physical and chemical properties of peat as a water storage container and to determine the correlation between volume weight, porosity, and water content. The method used is a descriptive method, Sieve analysis, using ring samples and eagle auger camp. Laboratory results show that the BD value is small, the PD value is small, the water content value is high, the peat has maturity levels of Sapric and Hemic, and the texture consists of coarse sand, medium sand, and fine sand > of dust, no silt or clay, has a relative ash content low, high organic matter. The correlation is that when the BD and PD values are low, high water content means high porosity, large water storage, drought easily during the dry season, so fires easily occur.

Unveiling the dynamic of nitrogen through migration and transformation patterns in the groundwater level fluctuation zone of a different hyporheic zone sediment

This study investigates the impact of water levels and soil texture on the migration and transformation of nitrate (NO3−-N) and ammonium (NH4+-N) within a soil column. The concentrations of NO3−-N gradually decreased from an initial concentration of 34.19 ± 0.86 mg/L to 14.33 ± 0.77 mg/L on day 70, exhibiting fluctuations and migration influenced by water levels and soil texture. Higher water levels were associated with decreased NO3−-N concentrations, while lower water levels resulted in increased concentrations. The retention and absorption capacity for NO3−-N were highest in fine sand soil, followed by medium sand and coarse sand, highlighting the significance of soil texture in nitrate movement and retention. The analysis of variance (ANOVA) confirmed statistically significant variations in pH, dissolve oxygen and oxidation–reduction potential across the soil columns (p < 0.05). Fluctuating water levels influenced the migration and transformation of NO3−-N, with distinct patterns observed in different soil textures. Water level fluctuations also impacted the migration and transformation of NH4+-N, with higher water levels associated with increased concentrations and lower water levels resulting in decreased concentrations. Among the soil types considered, medium sand exhibited the highest absorption capacity for NH4+-N. These findings underscore the significant roles of water levels, soil texture, and soil type in the migration, transformation, and absorption of nitrogen compounds within soil columns. The results contribute to a better understanding of nitrogen dynamics under varying water levels and environmental conditions, providing valuable insights into the patterns of nitrogen migration and transformation in small-scale soil column experiments.

Rhizospheric Fungal spp. of Tomato (Solanum lycopersicum L.) and Their Effect on Tomato Plant Growth and on Alternaria solani, the Causative Agent of Early Blight of Tomato

Tomato (Solanum lycopersicum L.) is a widely consumed crop throughout the world including Sri Lanka. Use of agrochemicals for enhanced yields and managing diseases associated with tomato results in deleterious impacts on soil microflora, fauna and leads to human health problems. A possible alternative is the use of rhizospheric microorganisms, as they are reported to improve productivity and protect various crops. Hence this study aimed to isolate rhizospheric fungal assemblages of tomato plants and evaluate their ability to solubilize phosphate while, controlling Alternaria solani, the causative agent of Early Blight of tomatoes. Rhizospheric fungi were isolated from commercial tomato cultivations in two agro-ecological zones (WM3b and IM2b), using soil dilution plate technique. Composite samples of soil attached to the root systems of five healthy plants, uprooted from each field were prepared and 10 g of each sample was used for the isolations. Twenty-seven fungal genera were isolated and Trichoderma and Penicillium were the frequently isolated genera. Phosphate solubilization ability of each fungal species was evaluated using Pikovskaya's agar and liquid medium, and four isolates (Eupenicillium sp., Talaromyces purpureogenus, Paecilomyces sp., and Purpureocillium lilacinum) with the highest phosphate solubilizing abilities were evaluated on tomato plant growth under greenhouse condition. The inocula of each fungal sp. were prepared by adding fifteen, 6mm diameter mycelial discs from each 5-day-old culture into polypropylene bags containing 90 g of sterile rice husk medium and incubated for 02 weeks at room temperature. Each pot contained a 4.6 kg layer of non- sieved sterilized potting medium (Sand: topsoil: Compost at 2:1:1 ratio) and a 2.5 kg layer of sieved medium on top, which was mixed with 15 g of inoculum. Three-week old, healthy tomato seedlings (variety-Bathiya) were planted (with 3 replicates) and allowed to grow with regular watering. Control pots contained potting medium with uninoculated sterile rice husk. Growth parameters such as Root and shoot lengths, fresh and dry weights of roots, shoots, and leaves were evaluated at 02-week intervals for 02 months and the results were analysed using ANOVA with Tukey‘s pairwise comparison. Plants treated with T. purpureogenus and P. lilacinum showed significant increases (p≤0.05) in all growth parameters in every evaluation. Dual culture plate assay on the Potato Dextrose Agar was used to test the effect of rhizospheric fungal spp. on the radial colony growth of A. solani, and Eupenicillium sp. showed the highest percentage inhibition (85.09±5.68%). Microscopic observations of inhibition zones between two colonies showed the presence of coils, loops, knobs, and haustoria, formed by inhibitory rhizospheric fungal species. Assays for Chitinase and Glucanase enzyme production showed that Mortierella sp.-1, P. lilacinum, Trichoderma sp.-1, and Acremonium sp. were the highest chitinase producers, whereas P. lilacinum was the highest glucanase producer. These results indicate the ability of some rhizospheric fungal species of tomato to increase the growth of tomato plants significantly by phosphate solubilization and ability to inhibit the growth of foliar pathogen A. solani under in vitro conditions. &#x0D; Keywords: Rhizospheric fungi, Phosphate solubilization, Dual culture plate, Plant growth parameters

Determination of aquifer hydraulic parameters and groundwater protective capacity in parts of Nsukwa clan, Nigeria.

The goal of this study is to determine aquifer parameters and groundwater protective capacity in parts of the Nsukwa clan using geoelectric and pumping test methods. Seventeen vertical electrical soundings were acquired to determine the geoelectric properties, while two wells were drilled to determine the lithology and the aquifer parameters of the area. The result showed that the lithology comprised lateritic topsoil and sand, fine sand, medium sand, and coarse sand, respectively. Geoelectric data interpretation using Win Resist software revealed a close correlation with the well record. Geoelectric data analysis indicated that prolific aquifer can be sourced within the third and fourth layers, located within 24.2-43.8m and comprised medium to coarse sand. The aquifer resistivity ranged from 703.1 to 26,367.7Ωm. The Dar Zarrouk parameters, such as transverse resistance (R) and longitudinal conductance (S), were applied to determine the aquifer transmissivity (T) and hydraulic conductivity (K). The computed T and K from geoelectric sounding ranged from 11.37 to 34.79m2/day, with a mean value of 18.51m2/day and 0.8243m/day, respectively, while the T and K values from the pumping test are 18.58m2/day and 0.8251m/day, respectively. S and R values ranged from 0.001179 to 0.0131619Ω-1 and 2434 to 102,090Ωm2, respectively, revealing a poor aquifer protective capacity and moderate yield. The storativity and storage coefficient of the aquifer values of 0.0023 and 0.072m2/min, respectively, revealed a confined aquifer capable of providing sufficient water to the people. These findings showed moderate aquifer potential with poor protective capacity; thus, adequate aquifer protective strategies are recommended.

Growth and Survival of Chilgoza Seedlings as Influenced by Different Types and Size of Sowing Media

Chilgoza pine (Pinus gerardiana Wall.) is an important but endangered tree species in Afghanistan. Due to poor natural regeneration, seed-related dormancy and anthropogenic factors, the IUCN put this species on the red list. Therefore, this study was undertaken to investigate the effect of growing medium and polybag sizes on seedling growth and survivability. In this study, four growing media of soil (So), compost (Co), forest soil (Fs) and sand (Sa), viz., M1 (So + Co + Fs); M2 (Fs + Co + Sa); M3 (So + Fs + Sa); and M4 (Sa + Co + Fs) and three polybag sizes including P1 (16 cm×16 cm), P2 (18 cm×18 cm), and P3 (21 cm×26 cm) were used and arranged in the frame of 4×3 factorial design to assess their effects on seedling growth and survivability. The results revealed that among different growing media treatments, higher seedling growth parameters and survival rate percentage were observed on treatment M4 (Sand + Compost + Forest Soil). Seedling growth parameters and survivability were significantly affected by polybag size, and the highest seedling growth parameters and survival rate were obtained for Large Polybag size (P3).

Wall-resolved large eddy simulation of mixed-size sand-laden flow

Most of the existing numerical studies on wind-blown sand flow simplify sands into single-size particles, whereas natural wind-blown sand flow is a two-phase flow with mixed-size particles, thus, the simulation of mixed-size sand-laden flow is necessary. In the present work, wall-resolved large eddy simulations of mixed-size sand-laden flows are realized. Each sand in the wind field is tracked using the Lagrangian point-particle model. The transport characteristics of sand particles in mixed-size sand-laden flow are investigated under the premise of considering bed erosion. Considering the significant influence of sand-bed collision on simulation, the splash function is modified in the present simulation according to the previous experimental results. It reveals that in mixed-size sand-laden flow, the fraction of rebound sand particles in all the saltation particles is approximately 0.6, which is twice times of the ejected sand particles, and the modification of the sand rebound angle greatly affects the simulation results of mixed-size sand-laden flow. Meanwhile, the mean size of the saltation sand particles decreases with height and is 20% lower at the top of the saltation layer than that near the sand bed in the present simulation. Further analysis by grouping of sands with their size shows that the sand transport intensity of small sands decreased more rapidly with increasing height. The volume fraction and sand transport intensity of small sand particles exceed those of medium and large sand particles at heights y/δ = 0.05 and y/δ = 0.1.

Assessment of sand dunes in Missan Governorate, South-eastern Iraq: Implications for Extraction High Purity Silica

Sand dunes are widely spread in Missan Governorate, South-eastern Iraq in many areas including; Manziliyah, Khazina, Zubadiate, and Chailat. X-ray diffraction (XRD) results of sand samples of sizes 0.063-2 mm, 0.125-0.250mm, and 0.250-0.500mm, revealed that quartz is the main mineral phase, followed by calcite, feldspar and trace of gypsum. Chemically SiO2 is the main oxide in sand of an average 61.36 % while the rest oxides; CaO (14.08%), Al2O3 (6. 76%), Fe2O3 (3.05%), K2O+Na2O (2.30 %) are considered as impurities that could affect the properties of sand. XRD tests indicated the formation of crystalline phase of synthetic silica. XRF showed an increases in SiO2 to 85.37%, while all other oxides (impurities) were reduced to their minimum rate, particularly CaO (1.06 %). Field emission scanning electron microscope (FESEM) and Brunauer-Emmett-Teller (BET) tests indicated the existence of well compiled spherical particles of synthetic silica within the size of 8.55 nm and surface area of 66.51 m2\\g. The medium sand size (0.250-0.500mm) is the appropriate size to produce high purity crystalline silica as it contains the greatest percentage of silica and the low percent of impurities compared to other sizes of sand.

Estimating the Peak Outflow and Maximum Erosion Rate during the Breach of Embankment Dam

Understanding and modeling a dam breaching process is an essential investigation, because it aims to minimize the flood’s hazards, and its impact on people and structures, using suitable mitigation plans. In the current study, three-dimensional numerical modeling is carried out using the FLOW-3D HYDRO program to investigate the impact of various factors, including the dam grain size materials, crest width, inflow discharge, and tail water depth on the dam breach process, particularly the peak outflow, and the erosion rate. The results show that changing the grain size of the dam material from fine sand to medium and coarse sand leads to an increase in the peak outflow discharge by 16.0% and the maximum erosion rate by 20.0%. Furthermore, increasing the dam crest width by 40% leads to a decrease in the peak outflow by 3.0% and the maximum erosion rates by 4.50%. Moreover, increasing the inflow discharge by 25.0% increases the peak outflow by 23.0% and the maximum erosion rates by 21.0%. Finally, increasing the tail water depth by 50.0% leads to decreasing the peak outflow by 4.50% and the maximum erosion rate by 43.0%. The study findings are considered of high importance for dam design and operation control. Moreover, the results can be applied for the optimum determination of the crest width and tail water depth that leads to improving the dam stability.

Standardization of Hydroponic Growing Media and Nutrient Solution Application Intervals for Optimal Growth in Syngonium podophyllum Schott. cv. ‘White Butterfly’

Hydroponics can be said as a way to skip soil. It is the method of growing plants in soilless media along with external supply of nutrient solutions. The selection of plants suitable for cultivation in indoor environments with restricted space is becoming increasingly crucial in contemporary times. Syngonium podophyllum Schott. cv. ‘White Butterfly’ is a very important plant in current scenario with bewitchingly beautiful ornamental foliage. Four types of soil less media were taken for the experiment including, metal jelly (10mm), vermiculite, expanded clay balls and quartz sand. 150% dose of Hoagland solution was applied to plants through drip system till it reach 70% field capacity. The nutrient solution was applied in four levels such as daily, alternate days, two days intervals and three days intervals. Growth parameters like number of leaves per plant, leaf area, plant height and number of roots were observed in every 15 days interval up to four months. Highest mean number of leaves were obtained for vermiculite media when nutrient solution was applied at daily interval basis at 120 DAP (16.8). This treatment was also found on par with alternate days nutrient solution application in combination with vermiculite media (14.6), daily nutrient solution application in metal jelly media (14) and alternate days nutrient solution application in quartz sand media (15.4). While clay ball media with alternate days interval of nutrient solution application was found superior in terms of leaf area (267.60 cm2), plant height (30.56cm) and root length (58.94 cm) characteristics at 120 DAP.

CONCENTRATION OF SUSPENDED SOLIDS BY SPECTROPHOTOMETRY

The use of sensors with optical principles designed to estimate sediment transport, and mainly the concentration of suspended solids (CSS) constitutes a robust technique that is currently consolidated and well disseminated in the scientific community, thus configuring an important tool in research, management and control of river basins. The present study, carried out in a water body located near the mouth of the Coxim River - (Coxim, MS), consisted of comparing Nephelometric Techniques and the integrated area of ​​absorbance at wavelengths in the spectrum from 400 to 600 mm (A400-600) and these are measured using a UV/VIS spectrophotometer for indirect determination of CSS. This water body showed characteristics of high sediment input; and for the purpose of possible relationships between the parameters and the characterization of suspended sediments transported by the river, the granulometry (Medium Sand, Fine Sand, Silt and Clay) of the processed samples was determined. The interactions between the parameters to indirectly determine CSS showed the following correlations: (p&lt;0.001); Nephelometric with (R=0.942) and A400-600 (R=0.959); and the particle size fractions, in turn, indicated: (%) of Silt (52.6 ± 17.4), in addition to values ​​close to the distribution of Clay (15.3 ± 6.73), Fine Sand (15.6 ± 10.83) and Medium Sand (16.7 ± 11.84). In this context, according to the results of the residues and correlations, it was observed that A400-600 behaved in a more allusive way compared to the Nephelometric technique in drought and flood events, thus estimating the Detection Limit for CSS (26 .47 mg.L-1 and 44.67 mg.L-1) respectively.

Grain size and heavy metal assessment in barchan dunes surrounding the Talatan PV power generation area, Qinghai Province

Heavy metal contamination in sediments near photovoltaic (PV) power generation areas poses potential environmental risks, requiring detailed characterization and source apportionment to facilitate sustainable management. This research explores the characteristics of sediment grains and the concentrations of heavy metals present in surface sediments from barchan dunes proximal to the Talatan Photovoltaic (PV) power generation area, located within Gonghe County, Qinghai Province. The sediments displayed an average grain size within the medium sand range, with marginal differences discernible between the windward and leeward slopes. With the exception of Mn, Cu, Zn, V, Pb, and Ba, concentrations of the remaining metals were found to surpass the baseline levels established by Chinese aeolian soil data, alluding to potential anthropogenic influences. Through employing coefficients of variation in multivariate statistical analysis, it was identified that the concentrations of Cr and Co were significantly elevated, suggesting potential anthropogenic contamination, which may be associated with photovoltaic industrial activities. Specifically, the elevated concentrations of Cr and Co suggested anthropogenic contamination, potentially associated with photovoltaic industrial activities. Utilizing a combination of Correlation Coefficient Analysis, Principal Component Analysis, and Cluster Analysis, three potential sources of heavy metals were identified: (1) industrial origin for elements such as Cu, Cr, Ni, Zn, and As; (2) elements with limited direct application in the photovoltaic industry but associated with materials and energy storage, namely Ba, V, and Mn; (3) anthropogenic inputs related to construction materials and battery storage systems in the photovoltaic park, specifically Co and Pb. The findings offer a significant understanding of the heavy metal characteristics and sources in proximity to the Talatan PV power generation area, emphasizing the impact of human activities on environmental quality. These insights underscore the necessity for enhanced monitoring and management of industrial activities to mitigate potential environmental impacts. Further research is recommended on a broader spatial scale to yield a more comprehensive understanding of this subject.

Sea turtle landing and distribution in aceh jaya district

The research in Aceh Jaya District identified nine turtle nesting beaches: Babah Kuala, Patek, Babah Ngom, Kuala Doe, Rigaih, Alue Piet, Nisero, Aroen Meubanja, and Seunebok Padang. Olive Ridley (Lepidochelys olivacea) and Leatherback (Dermochelys coriacea) turtles inhabit these coastal areas. Nisero beach, Kuta Tuha Village, Panga Sub-District, recorded the highest nest count (12 nests) with both Leatherback and Olive Ridley turtles. Seunebok Padang beach, Seunebok Padang Village, Teunom Sub-District, had the lowest count (2 Olive Ridley turtle nests). Aroen Meubanja beach is the only one with protected status, while the remaining eight face the threat of egg poaching. Unprotected beaches are at high risk, emphasizing the importance of conservation for sea turtle survival and the local economy, particularly through tourism development. Beyond Aceh Jaya, Indonesia features other significant sea turtle nesting sites, like Pangumbahan beach in West Java and Wairundi Island and Venu Island in West Papua Province. The study evaluates various beach characteristics, including width and slope, influencing sea turtle nesting activities. Sediment analysis reveals predominant medium sand textures in Aceh Jaya District, contributing to suitable nesting conditions and emphasizing the need for targeted conservation efforts.

Bedforms and sediment dynamics under reduced sediment input and estuarine engineering: the case of the Bou Regreg estuary, Morocco

The Bou Regreg riverine estuary constitutes a microtidal environment located within an urban region and characterized by limited sediment inflow from its catch basin hinterlands. The construction of the Sidi Mohamed Ben Abdellah (SMBA) dam has notably diminished sediment supply, especially coarser fractions. In light of these conditions, this study aimed to classify sediment types according to the Folk and Ward classification, stratify morphometric parameters and temporal fluctuations based on dune types, and ultimately evaluate the sediment dynamics driving observed bedform variations. Using an integrated approach, data collection involved various techniques, including CTD profiling, bottom videography, side-scan sonar imaging, sub-bottom profiling, and Van Veen bottom grab sampling. The bed morphology includes segments of smooth bed, erosional and dredged bottom, localized scour features, and submarine dune fields, displaying notable heterogeneity. Acoustic seabed reflections indicated two bedform clusters with maximum lengths of 42.6 m and heights of 1 m. Flow velocities were linked to the presence of 2D and 3D dune forms. Morphological variations encompassed straight, sinuous, and barchan dune configurations, mainly asymmetric with NNW–SSE seaward orientation. Sediment mean size fluctuations spanned from muddy to medium sand deposition. The findings revealed the intricate interplay of dynamics shaping dune field configurations and the heterogeneous dispersion of bedforms throughout the estuary likely due to a sharp decline of sediment discharge caused by the dam upstream and coastal engineering. The study emphasizes the dynamic nature of dunes, highlighting their sensitivity to shifting hydrodynamic conditions and sediment availability, leading to morphological fluctuations over time.

Control of Sediment Grainsize on Lead (Pb) Content in the Reef Sediment Systems: A Case Study of Panjang Island, Banten Bay, Indonesia

Sediments are known to accumulate pollutants from terrestrial and coastal waters, and can be used as an indicator to monitor metal pollution in the biosphere and the effects of anthropogenic events in the environment. Eight samples of reef surface sediments were collected from the north and east coasts of Panjang Island. Panjang Island, located to the north of Banten Bay, was chosen for this study because of its proximity to many industrial areas. Nevertheless, the island supports a natural ecosystem, including coral reefs, seagrass, and mangroves. The samples were analyzed for the grainsize, component analysis, and Pb concentrationusing AAS flame method. The result indicated Pb concentration in the grain-supported surface sediment in Panjang Island is varied. The detected Pb concentrations were 0-28.68 mg/kg in dry weight. The study indicated that the different concentration of Pb value is mainly controlled by the different of sediment grainsize. The highest Pb accumulation occurs in the areas with very fine sediment grainsize, which have better adsorption capabilities for heavy metals. This study also suggests that the medium sand fraction may accumulate different Pb values. The result indicated that, according to the classification of ANZECC/ARMCANZ, all sediment samples in the study area is in the low risk of toxicant level. Additionally, the SQG-Q (Sediment Quality Guidelines) quotient analysis indicates that Pb concentration in the study area posed a low-moderate impact to adverse biological effect.

Role of Hydrophilic Biopolymers Concoction Seed Coating on Seed Germination and Field Performance of Blackgram (Vigna mungo L.)

Background: Blackgrm is one of the most important pulse crops majorly cultivated in rainfed conditions of India. Soil moisture deficit,low and erratic rainfall, use of poor quality seeds,poor crop stand and improper crop managementresulting in lower productivity in rainfed ecosuystem . Reduced crop stand alone leads to 30% deficit in production combined.Availability of technology to overcome drought stress is one of the way to expand blackgram cultivation in dry tracks. Hydrophilic polymers may have great potential in restoration and reclamation, when used the polymers correctly and an ideal situations will have atleast 95 % of their stores water available for plant absorption. There are N number of inorganic polymers available in the market, that can be applied in the farm of soil application. Studies on Hydrophilic bio polymer seed coating to mitigate water stress is very megar or nil. Hence, the present study was formulated in blackgram as hydrophilic bio polymer seed coating on seed germination and field emergence. Method: Seed coating experiment consists of seven hydrophilic biopolymers (Ethyl cellulose, Methyl cellulose, Carboxyl methyl cellulose, Agar, Gum Arabic, Xanthangum and Carrageenan); two coating methods (dry and dry powder concoction). The germination test conducted in sand media with 60 % Water Holding Capacity of sand and PEG induced water stress and evaluated for seed quality parameters against uncoated seeds. Field experiments conducted with water stress periods of 10 days, 20 days and 25 days after life irrigation and observed for biometric and yield parameters. Results: Results revealed that blackgram seeds coated with bio polymer concoction of xanthan gum : carrageenan : agar agar (4:1:1) @ 20 g / kg performed better in terms of all seed quality parameters and withstand water stress upto 20 days after life irrigation with the yield increase of 53% over stressed control (skipping irrigation for 20 days after life irrigation) and can be recommended as a pre sowing treatment for drought mitigation in blackgram.

Experimental Study on the Filtration Characteristics and Sediment Distribution Influencing Factors of Sand Media Filters

The sand media filter is a crucial component of micro-irrigation filtration systems. Investigating the effects of various factors on filtration performance and the migration patterns of sediment particles within the filter can enhance the healthy operation of sand media filters. This study, based on a sand media filter model, conducts indoor hydraulic experiments, selecting different experimental factors and observation indices for research under varying conditions. Results indicate that filter thickness and raw water concentration are positively correlated with the turbidity of filtered water samples, while changes in filtration rate have no obvious impact on turbidity. When filter thickness is large, particle content differs obviously from other filter thicknesses, and the effect of raw water concentration changes on particle content is similar to that of filter thickness changes. Sediment particle size distribution within the filter layer is primarily concentrated in the upper region. By focusing on the area situated 20 cm below the filter layer surface, the sediment retention rate reached 80% or higher at a depth of 20 cm below the filter layer surface. As the depth of the filter layer increases, the sediment retention characteristics show a decreasing trend for larger particle sizes and an increasing trend for smaller particle sizes. Head loss is positively correlated with filtration rate, raw water concentrations, and filter thickness changes. It is suggested that, when meeting micro-irrigation water quality requirements, the filter material particle size can be appropriately increased to improve filtration efficiency and reduce energy consumption. These research findings are highly significant for sand media filter material selection and working condition design.

A novel combined system for efficient nitrate removal using a continuous flow electrocoagulation and sand filtration (FECF) reactor: Statistical analysis by Taguchi design.

In this study, a new hybrid bench-scale electrocoagulation-sand filtration (FECF) reactor was developed for purifying nitrate-contaminated samples. Before and after electrochemical treatment, two sand filters were included in this continuous system to facilitate the purification procedure, and the contaminated water flows horizontally through the entire system according to a specific hydraulic gradient within the reactor, resulting in water purification. Significant improvement in treatment performance was observed due to the presence of metal hydroxides in the second filter media that were not fully involved in the electrocoagulation treatment. Energy dispersive X-ray (EDX) analysis was performed to detect metal hydroxide species in the sand media, and the need for filter regeneration was evaluated by monitoring changes in the system flow rate. Moreover, an evaluation of the effects of different factors including operating time, current intensity, initial pH, type of anode and cathode, initial nitrate concentration, hydraulic head level inside the reactor, number of electrodes, and NaCl electrolyte concentration on the performance of nitrate removal was conducted through the Taguchi design. Further, ANOVA analysis verified the accuracy of the predicted model, and the variables were classified based on their relative importance in the FECF process. According to the regression model, 97% of nitrates were removed with Al electrodes as anode and Fe as cathode, 70 min purification time, current intensity of 3 A, 100 mg/l initial nitrate concentration, pH 8, electrolyte concentration of 1 g/l, electrode number of 6, and 1.5 cm head level.