Soil Amendment Research Articles

Potential Use of Conventionally Produced Low Technology Tea Pruning Litter Biochar as Soil Amendment: A Comparative Study

Potential Use of Conventionally Produced Low Technology Tea Pruning Litter Biochar as Soil Amendment: A Comparative Study

Assessment of the germination power and α-amylase activity in the soil rhizospheric compartment amended with olive mill waste waters.

Olive mill wastewater (OMWW) was used in ferti-irrigation due to its high water content, as well as its organic and mineral richness. However, this by-product also contains elevated levels of polyphenols, which may pose phytotoxic risks to soil microbiota and plants over time. To address this concern, we conducted a thorough examination of the phenolic composition of OMWW and the phenolic content of amended soils using HPLC analysis. Additionally, we assessed the residual phytotoxicity of OMWW across various soil rhizospheric layers (0-30 cm, 30-60 cm, and 60-90 cm). Standard germination tests were performed using soil extracts with sorghum (Sorghum bicolor) and tomato (Solanum lycopersicum) seeds. We also measured α-amylase activities in the germinated seeds for both species, comparing them to raw OMWW and control soil extracts. HPLC analysis revealed that tyrosol, ferulic acid, and hydroxytyrosol were the predominant phenolic compounds in crude OMWW, while no detectable compounds were found in the soil extracts. Germination tests indicated minimal toxicity in the topsoil amended with OMWW, with a noticeable reduction in residual phytotoxicity at greater depths. These results aligned with the α-amylase activity assessments, which demonstrated significantly higher enzyme activity in the deeper soil layers (30-60 cm and 60-90 cm), with no substantial differences compared to control extracts.

Effects of Fresh and Composted Azolla on Soil Chemical Properties

The rise in chemical fertilizer use in Malaysia raises concerns about soil degradation and potential long-term yield reductions, highlighting the importance of using organic matter for soil restoration. Azolla has been extensively studied as an alternative soil amendment due to its high nitrogen and nutrient content, as well as its rapid growth. However, the effects of fresh and composted Azolla amendments on soil chemical properties are not yet fully understood. A soil incubation study was thus conducted to determine the effects of fresh and composted Azolla on soil chemical properties over a 3-month incubation period. The soil treatments consisted of non-amended soil (control); fresh Azolla at 3, 6, and 9% w/w; and composted Azolla at 1, 2, and 3% w/w, with soil water holding capacity maintained at 55% throughout the incubation period. The collected soil samples were analyzed for soil pH and electrical conductivity (EC), total carbon (C) and nitrogen (N), available phosphorus, exchangeable bases—potassium (K), calcium, and magnesium, using inductively coupled plasma optical emission spectrometry, and cation exchange capacity (CEC). All data were subjected to variance analysis for statistical analysis. The study revealed significant effects of interaction between soil treatments and incubation periods for all soil parameters. At the end of the incubation period, the soil treated with 3% composted Azolla exhibited higher soil EC, total C and N, exchangeable K, and CEC compared to other soil treatments. The 3% fresh Azolla treatments were also observed to improve the soil’s exchangeable calcium by the end of the incubation period. In conclusion, 3% composted Azolla is best to help restore soil nutrient levels for crop uptake.

Variation in microbial communities and network ecological clusters driven by soil organic carbon in an inshore saline soil amended with hydrochar in Yellow River Delta, China.

Char materials (e.g., hydrochar) can enhance carbon sequestration, improve soil quality and modulate soil microbial communities to recuperate soil health. However, little is known about the soil organic carbon (SOC) content, as well as the microbial communities and co-occurrence networks in response to hydrochar amendment in an inshore saline soil. Here, the effect of Sesbania cannabina (a halophyte) straw derived hydrochar (SHC) amendment on SOC and labile organic carbon (LOC) fractions and the potential associations among SOC content change, soil C-cycling enzyme activities and microbial communities were illustrated using a pot experiment. SHC effectively improved the contents of SOC and LOC, particularly particulate organic carbon (POC), and stimulated the activities of C-cycling enzymes. Furthermore, SHC induced shift in microbial community compositions and co-occurrence networks, result in decrease in relative abundance of Actinobacteriota and its corresponding ecological cluster, which may favor SOC accumulation. Functional annotation of prokaryotic taxa (FAPROTAX) analysis also revealed a decrease in microbial ecological function related to carbon degradation. These findings provided a deeper insight about the hydrochar-induced SOC enhancement and suggested an efficient approach to improve C sequestration and improve soil health in the coastal salt-affected soil.

Impact of Soil Amendments and Improved Alkaline Water on the Physico-chemical Characteristics of the Soil, the Distribution of Salt in the Soil, the Growth, and the Yield of Hybrid Cotton Grown in Sodic Soil with Drip Irrigation

The effects of ameliorated alkali water and soil amendments on the soil properties, growth, and yield of hybrid cotton in sodic soil under drip irrigation were investigated in this field experiment at Anbil Dharma lingam Agricultural College and Research Institute, Trichy, using cotton (RCH-20) as a test crop. The main-plot treatments included drip irrigation with gypsum treatment water and drip irrigation with spent wash treatment water; the sub-plot treatments included soil application of gypsum @ 50% GR (5.2 t ha-1) and a one-time soil application of distillery spent wash at 5 lakh liters ha-1. The treatment without amendments under main plot and sub-plots was used as a control. The experiment was designed in a strip-plot design with four replications. The application of additives through irrigation water or soil dramatically lowered the post-harvest soil's pH. Plots applied with wasted wash had the greatest pH reduction (M1S1) 7.81, followed by those applied with gypsum (M2S2) 7.90 and control (M3S3) 8.15. Because there was more soluble salt present in the spent wash treated plots, there was a little rise in EC. Drip irrigation with distillery spent wash (DSW) treated water and drip irrigation with gypsum treated water, respectively, resulted in ESP decreases of (M2S2) 0.97 and (M1S1) 0.61 over control. Similarly, ESP decreased by 2.63 and 1.31 when gypsum and DSW were applied to the soil, respectively, compared to the control. The organic carbon values ranged from (M3S3) 0.47 to (M2S2) 0.92 percent. In general, an increase in organic carbon content was observed in all the treatments that received amendments (Gypsum& DSW) compared to control. Salt distribution pattern conducted in treatment of distillery spent wash @ 5.0 lakh liters ha-1 significantly increased vertical depth of soil pH ranges (7.56,7.68,7.80,8.30) and decreased EC ranges (1.05,1.02,1.00,0.95) followed by horizontal line soil pH ranges (7.54,7.51,7.49,7.50) and EC ranges (1.04,1.02,1.00,1.02) at 120 DAS after application. In the experimental field recorded vertical depth of soil increased pH and decreased electrical conductivity compared to horizontal distances of soil pH and EC. The physico- chemical properties reduced in treatment one time application of DSW @ 5 lakh liters ha-1 recorded the highest physico -chemical properties followed by the treatment receiving irrigation with gypsum bed treated alkali water and lowest was recorded in the untreated alkali water irrigated through drip system in non- amended soil.

Effect of gypsum on transport of IMX-104 constituents in overland flow under simulated rainfall.

Residue of energetic formulations, which is deposited on military training grounds following incomplete detonation, poses biotic hazards. This residue can be transported off-site, adsorb to soil clays and organic matter, transform or degrade, or taken up by plants and animals. Its harmful effects can be mitigated by localizing the energetics at the site of initial deposition using soil amendments and allowing them to bio- and photodegrade in situ. Small plots with coarse loamy soil were used to study the effect of gypsum (CaSO4·2H2O) on transport and redistribution under simulated rainfall of various sizes of insensitive munition explosive (IMX)-104 particles, which consist of 3-nitro-1,2,4-triazol-5-one (NTO), 2,4-dinitroanisole (DNAN), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), and octahydro-1,3,5,7-tertranitro-1,3,5,7-tetrazocine (HMX). The addition of gypsum more than doubled infiltration and decreased sediment loss by 16% compared to the control. The post-rainfall mass balance of IMX-104 in the order from greater to smaller pools was as follows: (1) soil surface retention, (2) off-site loss to overland flow, and (3) sub-surface infiltration. Overall, the application of gypsum significantly decreased concentration and the total mass loss of dissolved DNAN, RDX, and HMX in surface runoff. In addition, gypsum significantly decreased (for NTO, DNAN, and HMX) or delayed (for NTO, DNAN, RDX, and HMX) the peak discharge of <2mm particulate energetics. The infiltration of NTO in the gypsum treatment was fivefold greater than in the control. Moreover, DNAN and RDX were also present in infiltration, while in the gypsum-free control none were found. Gypsum shifted the total mass balance of energetics toward subsurface flow. This study indicates that gypsum may decrease off-site transport of energetic constituents in the soils that are subject to surface sealing.

Biochar co-compost increases the productivity of Brassica napus by improving antioxidant activities and soil health and reducing lead uptake

Lead (Pb) is a serious toxic metal without any beneficial role in the biological system. Biochar (BC) has emerged as an excellent soil amendment to mitigate Pb toxicity. The impact of BC co-compost (BCC) in mitigating the toxic impacts of Pb has not been studied yet. Therefore, this study aimed to evaluate the potential of BC and BCC in improving the growth, physiological, and biochemical traits of Brassica napus and soil properties and reducing health risks (HR). The study was comprised of different Pb concentrations (control and 100 mg kg-1) and organic amendments (control, BC, compost, and BCC). The results indicated that Pb stress reduced the growth, photosynthetic pigments, seed yield, and oil contents by increasing hydrogen peroxide (H2O2) production and Pb uptake and accumulation in plant tissues and decreasing photosynthetic pigment and nutrient availability. The application of BCC alleviated the adverse impacts of Pb and improved seed production (40.24%) and oil yield (11.06%) by increasing chlorophyll a (43.18%) and chlorophyll b (25.58%) synthesis, relative water content (23.89%), total soluble protein (TSP: 23.14%), free amino acids (FAA: 26.47%), proline (30.98%), APX (40.90%), CAT (32.79%), POD (24.93%), and SOD (33.30%) activity. Biochar co-compost-mediated increase in seed and oil yield was also linked with a reduced accumulation of Pb in plant parts and soil Pb availability and improved the soil-available phosphorus, potassium, total nitrogen, soil organic carbon (SOC), and microbial biomass carbon (MBC). Furthermore, BCC also reduced the bioaccumulation concentration, daily metal intake, hazard index, and target hazard quotient. In conclusion, application of BCC can increase the growth, yield, and oil contents of Brassica napus by improving the physiological and biochemical traits and soil properties and reducing the Pb uptake.

Bioremediation of Spent Engine Oil Polluted Soil Enhanced with Blends of Poultry Manure and Pig Dung

The disposal of spent oil into open vacant plots and farms, gutters and water drains is an environmental risk. This study was conducted to explore the bioremediation of spent engine oil polluted soil enhanced with blends of poultry manure and pig dung, as well as its effects on microbiological composition of the soil. Top soil (0-15 cm depth) samples were collected from areas with history of spent engine oil contamination within Anyigba, Kogi State, Nigeria. One kilogram of soil was measured into nine clean dry containers of three litres each. The prepared blends of poultry manure and pig dung (PMPD) was mixed with the soil samples at the rate of 0, 50 and 100 g kg-1 soil in triplicates. The experiment used a Completely Randomized Design. Soil samples were taken from each container at 0 and 28 days for hydrocarbon utilizing bacteria and total petroleum hydrocarbon determination using standard methods. Data obtained from the experiment were subjected to descriptive and inferential statistics. The species identified were Enterobacter sp and Pseudomonas aeuginosa. Enterobacter sp was the most predominant isolate. The total petroleum hydrocarbon (mgkg-1) of the soil on day 0 was 59.78±1.84. After the amendments (at control, 50 and 100 g kg-1), the total petroleum hydrocarbon (mgkg-1) values were 44.92 ±2.26, 35.54 ± 2.78 and 29.52±1.28 at 28 days respectively. The blends of PMPD and the high level carbon utilizing bacteria, Enterobacter sp, showed promising potentials in the bioremediation of spent engine oil polluted soil by significantly enhancing the biodegradation process, as an impressive 50.62% remediation efficiency was achieved 28 days after amendment in soil treated with 100g of PMPD blend.

Agronomic Practices for Management of Ginger Bacterial wilt Disease: A Review

Ginger is one of the most important spices, particularly for small-scale farmers in Ethiopia. However, bacterial wilt is a major constraint to ginger production, and it was reported for the first time in 2012. The disease is caused by the bacteria &amp;lt;i&amp;gt;Ralstonia&amp;lt;/i&amp;gt; &amp;lt;i&amp;gt;solanacearum&amp;lt;/i&amp;gt;. Common symptoms in infected plants include wilting, stunting, yellowing of foliage, and rhizome rot. The disease is now widespread across all ginger-growing regions worldwide, spreading through soil, water, infected rhizomes, and plant debris. A major challenge in managing bacterial wilt has been the lack of effective control methods. This review primarily focuses on recent advances in control measures, including agronomic and cultural practices such as soil amendment, rhizome treatment, and other cultural practices. Soil and rhizome solarization has proven to be a cost-effective method that is compatible with other pest management tactics. Furthermore, the use of organic matter such as crop residue and animal manure has been investigated as a means of inducing &amp;lt;i&amp;gt;R. solanacearum&amp;lt;/i&amp;gt; suppression since it enhances the physical, chemical, and biological characteristics of soil. The application of certain plants and their essential oils as bio-fumigants has also been examined as an alternative approach to managing bacterial wilt as part of an integrated disease management system. Crop rotation, tillage, and field sanitation play vital roles in disease management. Furthermore, other farm practices, such as the use of healthy seeds, cultivation in disease-free areas, cover crops, bio-mulch, and regular field inspection, also contribute to the suppression of this pathogen. Overall, employing agronomic and cultural practices in combination with an integrated disease management strategy offers a promising approach for controlling bacterial wilt and ensuring sustainable ginger production.

Acidified biochar one-off application for saline-alkali soil improvement: A three-year field trial evaluating the persistence of effects

Salinization is a global soil degradation issue threatening agricultural productivity and environmental sustainability. Native biochar is a promising soil amendment, but its high alkalinity limits its use in saline-alkali lands. Acidified biochar, with a lower pH, is theoretically more suitable. This study aims to evaluate the persistence of effects of acidified biochar one-off application on soil particle size distribution, physicochemical properties, water retention, temperature regulation, and evaporation conditions of saline-alkali soil, thereby verifying its feasibility and exploring the optimal application range. We conducted a three-year cotton field experiment using palm fruit branch biochar as the raw material, acidified with ferrous sulfate, which involved four biochar applications (0, 10, 20, and 30 t ha−1) and four irrigation quotas (60 %, 80 %, 100 % and 120 % ETc). The results indicated that the initial acidified biochar application slightly increased surface soil (0–20 cm) pH by 0.1 %–3.9 %, this negative effect was nearly eliminated by the third year. Biochar application significantly altered surface soil particle size distribution, increasing sand content by 1.6 %–8.4 %, and persistently improved soil hydraulic properties, with water holding capacity still showing a 6.5 %–16.7 % increase in the third year. Biochar enhanced soil thermal insulation and suppressed soil evaporation, but these benefits gradually diminished with increasing cultivation years. Acidified biochar effectiveness was closely linked to irrigation quota. Significant differences in soil water and heat indicators were observed between the 20 and 30 t ha⁻¹ biochar treatments only under low irrigation quotas. Under sufficient irrigation (100 % and 120 % ETc), the optimal biochar application range was 15–20 t ha⁻¹, while under low irrigation (60 % and 80 % ETc), the optimal range was 20–25 t ha⁻¹. This study demonstrated that acidified biochar one-off application has significant multi-year benefits in improving soil structure and hydrothermal properties, providing a scientific basis for the improvement and sustainable utilization of saline-alkali soil.

Sustainable Wheat Cultivation in Sandy Soils: Impact of Organic and Biofertilizer Use on Soil Health and Crop Yield

Sandy soils are widespread globally and are increasingly utilized to meet the demands of a growing population and urbanization for food, fiber, energy, and other essential services. However, their poor water and nutrient retention makes crop cultivation challenging. This study evaluated the effects of integrating compost and plant growth-promoting rhizobacteria (PGPR; Azospirillum brasilense SWERI 111 and Azotobacter chroococcum OR512393) on wheat (Triticum aestivum L. var. Misr 1) grown in sandy soil under varying levels of recommended NPK (50%, 75%, and 100%) fertilization. Conducted over two growing seasons, the experiment aimed to assess soil health, nutrient uptake, microbial activity, and plant productivity in response to compost and PGPR treatments. The results demonstrated that combining compost and PGPR significantly improved soil chemical properties, such as reducing soil pH, electrical conductivity (ECe), and sodium adsorption ratio (SAR), while enhancing soil organic matter (SOM). Additionally, compost and PGPR improved soil nutrient content (N, P, K) and boosted the total bacterial and fungal counts. The combined treatment also increased urease and phosphatase enzyme activities, contributing to enhanced nutrient availability. Notably, plant productivity was enhanced with compost and PGPR, reflected by increased chlorophyll and reduced proline content, along with improved grain and straw yields. Overall, the results underscore the potential of compost and PGPR as effective, sustainable soil amendments to support wheat growth under varying NPK levels.

Positive impacts of compost and biochar from orange peel waste on Phaseolus vulgaris physio-biochemistry and productivity and soil properties under salinity stress

ABSTRACT Bioconversion of organic orange peel wastes into compost (OPC) or biochar (OPB) can help overcome the effects of soil salinity and maintain agricultural productivity. Effect of 1.0% OPC or 1.0% OPB as soil amendments on soil properties and performance of Phaseolus vulgaris plants under two salinity levels [5.60 dS m−1 (S-1) and 9.60 dS m−1 (S-2)] versus control [1.60 dS m−1 (S-0)] was investigated. Compared to the control, S-1 and S-2 increased soil sodium ion (Na+) content, while reducing soil organic matter (OM), macro- and micro-nutrients, cation exchange capacity (CEC), and enzyme (urease, acid phosphatase, and alkaline phosphatase) activities, reflecting decreased plant growth and yield. Under S-1 or S-2, OPC application exceeded OPB application, but both considerably enhanced soil OM content, nutrients, CEC, and enzyme activities. These positive results reflected decreased leaf electrolyte leakage and increased leaf-relative water content, pigments, nutrients, K+/Na+ ratio, antioxidant activity, plant growth, and yield. The beneficial impacts of 1.0% OPC were more pronounced under S-2 than S-1 or S-0. In conclusion, adding 1.0% OPC to saline soil (ECe of about 5–10 dS m−1) could mitigate the influences of soil salinity to improve Phaseolus vulgaris growth, physio-biochemistry, and yield.

Advancing Circular Economy in Olive Oil Production: Comparing Maturation Systems for Vermicompost Creation from Olive Pomace

The production of extra virgin olive oil (EVOO) creates by-products like olive pomace, which brings environmental issues due to its strong odors and the challenges involved in storage. To address this within a circular economy framework, this study explores the potential of olive pomace as a nutrient source for earthworms, aiming to transform it into a beneficial soil amendment. Key nutrients in the pomace, such as polyphenols, sugars, and organic matter, were examined for their effectiveness in nourishing earthworms. Four distinct treatments were applied to the pomace: mechanical mixing, aeration, a combination of both, and no treatment. For a period of 30 days, chemical parameters including pH, polyphenol levels, and moisture content were monitored, while earthworm preferences were assessed at Centro Lombricoltura Toscano (CLT). The study revealed significant differences in the chemical composition of the pomace depending on the treatment, especially regarding polyphenol and total sugar content. These changes influenced the palatability for earthworms, with the combined treatment producing the most appealing pomace, likely due to the increased nutrient availability. Ultimately, olive pomace has promising potential to be repurposed into a nutrient-dense soil amendment, alleviating environmental concerns and contributing to more sustainable waste management within the olive oil industry.

Nitrogen and Carbon Mineralization from Organic Amendments and Fertilizers Using Incubations with Sandy Soils

Synthetic fertilizers are the main nitrogen (N) input used in specialty crop systems established on sandy soils of Florida, although organic amendments and fertilizers can be used as a substitute. Organic N contained in these products must be mineralized before crop uptake, which is affected by amendment properties, soil properties, and temperature. A better method for predicting N release can help maximize the nutrient cycling benefits of organic amendments and fertilizers while avoiding negative environmental impacts. The main objective of this study was to measure N release and CO2 emissions from two poultry manure-based amendments (PMA) and two processed organic fertilizers (OF) made from livestock byproducts (e.g., feather meal). We conducted an 8-week incubation using two sandy Florida soils belonging to two soil orders (Entisol and Spodosol) and with a greater than two-fold difference in soil organic C. We incubated these soils at 10 °C, 17 °C, 24 °C, and 30 °C, measured plant-available N at 0, 1, 4, and 8 weeks, and measured CO2 emissions weekly. In both soils, OF released more inorganic N and at a faster rate compared with PMA, but CO2 emissions were greater from PMA than OF. Nitrogen mineralization and CO2 emissions increased with temperature, but temperature effects were less important than expected. These results on the mineralization of PMA and OF in sandy soils are key to optimize their use and management in Florida and other areas dominated by sandy soils.

Developing Guidelines for Azolla microphylla Production as Compost for Sustainable Agriculture

Azolla is a substitute compost that has the potential to enhance nutrient cycling in agricultural systems for sustainable development. In this study, four experiments were conducted to compare the Department of Agriculture (DOA, Thailand) ‘s methodology for determining the suitable type and rate of animal manure and the optimal light intensity for the growth and yield of Azolla (Azolla microphylla). The results revealed that applying 100% pig manure gave the highest yield of Azolla compared to the other manures. However, there was no discernible (p &gt; 0.05) difference in yield across the various doses (20.16, 30.16, and 40.16 gN m−2) of pig manure treatments, for which the minimal pig manure dosage of 20.16 gN m−2 was chosen. For further experimentation in the optimal light intensity, the 40% shading gave the highest yield of Azolla compared to no shading or 20 and 60% shading (p ≤ 0.01). When compared with the DOA Thailand methodology (1.27 kg m−2 of cow manure and covered with a size 32 mesh net), the findings indicated that the modified method (20.16 gN m−2 of pig manure + 40% shading) gave a 16% greater Azolla yield than that under the DOA Thailand methodology. The current finding method can produce a monthly fresh biomass of A. microphylla of 40.7 t ha−1 year−1 with higher contents of total N (4.92%) and lower C:N ratio (≤10:1) that could release minerals relatively rapidly. Its use can be encouraged by farmers to produce their own ecofriendly biofertilizer or soil amendment for sustainable agriculture.

Characterization of Biochar Produced from Cassava Stem

This project focuses on the characterization of biochar derived from cassava stem, a sustainable and abundant agricultural waste. The production of biochar through pyrolysis offers a promising solution for waste management, soil improvement, and carbon sequestration. The study aims to evaluate the physicochemical properties of the biochar, including its surface area, porosity, pH, nutrient content, and elemental composition. Analytical techniques such as scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) will be employed to investigate its structural and functional characteristics. Additionally, the research will explore the influence of pyrolysis conditions—temperature, heating rate, and residence time—on biochar quality. The potential application of cassava stem biochar as a soil amendment, its impact on soil fertility, and its role in reducing greenhouse gas emissions will also be investigated. By characterizing the biochar, this project seeks to promote the use of agricultural residues in sustainable practices and contribute to a circular bioeconomy.

Analysis of Nitrogen and Phosphorus Flows in a Rice-Growing Basin: The Case of the Maga Production Basin (Cameroon)

The availability of irrigation water has favored the development of agriculture in the Maga area, located in the Far North of Cameroon, with rice growing as the dominant agricultural activity. This activity is, however, known as a source of groundwater pollution through the infiltration of substances contained in inputs used for soil fertilization. The present study is a contribution to the analysis of the sources of contamination of the waters of the Maga rice basin by nitrogen and phosphate mineral compounds as well as the spatial distribution of these compounds. The monitoring of a network of fifteen wells and boreholes covering the rice-growing area during six campaigns made it possible to carry out the physicochemical characterization of subsurface and groundwater. The results obtained reveal that nitrates (NO3−) are present in water in low quantities, with averages per campaign ranging from 9.01 mg/L to 20.31 mg/L. On the other hand, ammonium (NH4+) and phosphates (PO43−) are in significant concentration. Their averages are of the order of 2.62 mg/L to 4.51 mg/L and then 0.65 mg/L to 5.58 mg/L for ammonium and phosphates, respectively. Mineral fertilizers used for soil amendment and degradation of organic matter, as well as the hydrolysis of minerals contained in the soil, contribute to the mineralization of water in the study area.

Evaluating corn, tall fescue and canola growth on sediments dredged from the Lorain Harbor

AbstractSoil degradation is a worldwide problem, causing the declining performance of many plant species. Recently, the application of sediments dredged from aquatic waterways has received attention for their potential as an organic amendment to revive degraded agricultural soils. In Ohio, dredged sediment research has largely focused on the success of corn (Zea mays) or soybean (Glycine max) following the application of dredged sediments from the Toledo Harbor, neglecting the potential for dredged sediments from the other eight harbors and waterways to change plant performance as well as failing to quantify benefits for other commonly grown crops in the region. In a greenhouse experiment, we applied dredged sediments from the Lorain Harbor to degraded agricultural soils across a variety of application ratios and quantified changes in germination, height over the growing season, final biomass, and yield for canola (Brassica napus), tall fescue KY 31 (Festuca arundinacea), and corn to better understand the potential for dredged sediments from this location to increase performance for a variety of regionally important plant species. Overall, plants grown on agricultural soils supplemented with dredged sediments from the Lorain Harbor consistently grew taller, faster, and were larger than the 100% dredged sediment treatments. Furthermore, both corn and tall fescue grown on agricultural soil supplemented with dredged sediments had greater yield compared to their counterparts grown on unamended agricultural soil. In whole, outcomes from this research contribute to a growing body of research that support the use of dredged sediments as a soil amendment for agricultural soils.

Delineation and Mapping of Groundwater Quality Assessment in Salem District, Tamil Nadu, India using GIS Techniques

Groundwater is a crucial natural resource with significant economic importance, supporting industrial activities, irrigation, and drinking water supplies. However, its extensive use for these purposes depletes water tables, which diminishes its future availability and leads to increased salinity, stream depletion, and land subsidence. A study was conducted to evaluate and map groundwater quality across different blocks in Salem district viz., Salem, Gangavalli, Thalaivasal, Attur, Pethanaickenpalayam, Valappady, Ayothiyapattinam, Yercaud, Panamarathupatty, Veerapandi, Edappadi, Sankari, Kadayampatti, Kolathur, Konganapuram, Magudanchavadi, Mecheri, Nangavalli, Omalur, and Tharamangalam. Sampling was conducted in February 2024, during which a total of 200 samples were collected and examined for pH, electrical conductivity, cations like Ca2+, Mg2+, Na+ and K+, anions like CO32-, HCO3-, SO42-, and Cl-. Based on the ionic concentration, the water quality parameters are derived such as Sodium Adsorption Ratio(SAR) and Residual Sodium Carbonate (RSC). The pH and EC values were ranged from 7.08 to 8.58 and 0.74 to 2.75 dS/m, respectively. The residual sodium carbonate (RSC) concentration ranged from -7.3 to 10.1 meq/L, while the sodium adsorption ratio (SAR) ranged from 0.7 to 9.7 meq/L. According to the CSSRI, Karnal Water Quality Classification, approximately 66.5 % of the samples fit into the good quality category, approximately 13% of the samples fit into the alkaline water category, and 20% of the samples fit into the saline water category in the Salem district. Using this classification, thematic maps depicting groundwater quality in the Salem district were generated with ArcGIS software. The study concludes that the majority of the samples are classified as good-quality water, while saline and alkali water emerge as the next major concern. Using this saline water for irrigation can change the soil's physical properties and lower agricultural productivity. Thus, it's crucial to apply soil amendments like gypsum and provide proper drainage to avoid long-term soil damage.

Biochar and nanoscale silicon synergistically alleviate arsenic toxicity and enhance productivity in chili peppers (Capsicum annuum L.)

Arsenic (As) contamination in agricultural soils threatens crop productivity and food safety. In this study, we examined the efficacy of biochar (BC) and silicon nanoparticles (SiNPs) as environmentally sustainable soil amendments to alleviate As toxicity in chili (Capsicum annuum L.) plants. Our findings revealed that As stress severely inhibited the growth parameters of Capsicum annuum L., and subsequently reduced yield. However, the application of BC and SiNPs into the contaminated soil significantly reversed these negative effects, promoting plant length and biomass, particularly when applied together in a synergistic manner. Arsenic stress led to increased oxidative damage, as evidenced by a 29% increase in leaf malondialdehyde content as compared to the healthy plants. Nevertheless, the synergistic (BC + SiNPs) application effectively modulated antioxidant enzyme activity, resulting in a remarkable 55% and 66% enhancement in the superoxide dismutase and catalase levels, respectively, boosting chili's resistance against oxidative stress. Similarly, BC + SiNPs amendments improved photosynthesis by 52%, stomatal conductance by 39%, soluble sugars by 42%, and proteins by 30% as compared with those of control treatment. Additionally, the combined BC + SiNPs application significantly reduced root As content by 61% and straw As by 37% as compared with the control one. Transmission electron microscopy confirmed that the synergistic use of BC and SiNPs preserved chili leaf ultrastructure, shielding against As-induced damage. Overall, the supplementation of contaminated soil with BC and SiNPs was proved to be a sustainable strategy for mitigating As toxicity in chili peppers, enhancing plant growth, physiology, and yield, and thereby food safety.