Soil Enrichment Research Articles

More is not always better: Impact of nutrient-addition on floral traits important for buzz pollination

Nutrient addition can affect plant fitness by altering resource allocation to reproduction or modifying floral traits. Alterations in floral attributes, particularly in species that exhibit specialization in specific ecological niches, can disrupt or augment the dynamics of interactions between plants and their pollinators. However, very little is known about how soil enrichment affects the floral characteristics and pollen release dynamics of buzz pollinated plants. Our study analyzed the effects of nutrient enrichment on the reproductive traits of a buzz pollinated plant species. Under greenhouse conditions, we established a phosphorus-rich nutrient gradient to investigate the impact of such enrichment on tomato plants (Solanum lycopersicum). Our study focused on: i) flowering patterns, ii) flower morphology, iii) pollen release from anthers, and iv) pollen quantity and quality (protein concentration). Plants were grown in low, intermediate, and high nutrient conditions, and various functional traits that are essential for buzz pollination were examined. Adding nutrients improved the display of flowers. Morphometric traits important for pollinator attraction and interaction, such as floral diameter, anther-tube width, and petal width, showed an increase in the high nutrient condition. The pollen quality and quantity were found to be unaltered; however, flowers originating from intermediate and high nutrient conditions exhibited reduced pollen release upon buzzing despite possessing ample pollen reserves. Our findings suggest that the positive effects of nutrient addition on floral traits are limited to a narrow range of concentrations. Higher concentrations can diminish these effects and impact the accessibility of pollen, as well as the reproductive performance of plants. In conclusion, based on our results, we predict that changing land use scenarios leading to nutrient accumulation may have significant consequences for plant-pollinator interactions.

Characterization and Remediation Potential of Sorghum and Rice Straw-Derived Biochars on Incubated Spent-Oil Contaminated Soil

The volume and spread of spent lubricants that are indiscriminately let into the environment in developing countries are prohibitive for soil health and productivity, adversely altering soil structure, permeability and microbiota. These result to loss of arable lands and low vegetation cover, thereby contributing significantly to food insecurity and global warming. Biochars possess sustainable soil amendment potentials that depend on the choice of feedstocks. This study used suitable analytical techniques to characterize biochars derived from sorghum and rice straw after slow pyrolysis at 550°C for three hours and investigated their effects on the physicochemical properties of spent oil-contaminated soil in an incubation experiment. Both sorghum biochar (SB) and rice biochar (RB) have pH in the alkaline range (˃ 8.0), similar O/C ratio (0.24), and significant proportions of carbon (53.87–57.57%). Scanning electron microscopy of SB and RB surfaces revealed presence of porous structures. Fourier Transform Infrared Spectroscopy revealed presence of carboxyl, hydroxyl, halogens, and sulphur on the surfaces of SB and RB which are responsible for heavy metal adsorption. Compared with control, increasing biochar amendment at 1, 2 and 3% significantly increased the porosity, water holding capacity and pH of the soil. Besides, soil Fe increased while the extractable content of heavy metals decreased. From this study, the properties of SB and RB and corresponding application in spent oil-contaminated soil indicate their suitability for soil enrichment and amendment.

Drip irrigation impacts on the root zone soil environment and enrichment characteristics of heavy metals in soybean

Drip irrigation impacts on the root zone soil environment and enrichment characteristics of heavy metals in soybean

Heavy metal contamination and health risk assessment of horticultural crops in two sub-cities of Addis Ababa, Ethiopia

This particular study was aimed to establish the level of heavy metals in different horticultural crops cultivated by irrigation and the soil in two sub-cities of Addis Ababa, Ethiopia, and quantitatively assess the health treat they pose for the consumer. A total of 151 vegetable samples comprised of lettuce (Lactuca sativa), cabbage (Brassica oleracea var. capitate), cucumber (Cucumis sativus), potato (Solanum tuberosum), parsley (Petroselinum crispum), Swiss chard (Beta vulgaris subsp. vulgaris), beetroot (Beta vulgaris), green onion (Allium porrum L.) and 28 soil samples were collected for this study. Six toxic elements were analyzed using microwave plasma atomic emission spectroscopy (MP-AES) after microwave assisted digestion of the samples. The concentrations of examined trace elements in vegetables (mg/kg) were found in the range of 5.50–93.00 for zinc; below detection limit (BDL)− 18.50 for copper; BDL-2.50 for nickel; BDL-17.00 for lead; 5.00–4256.50 for manganese and 22.00–8708.00 for iron. Considering the mean Pb content values, all vegetables exceeded the maximum permissible level set by the joint FAO/WHO commission in both irrigation sites. In case of Mn parsley, swiss chard, and green onion all from site two exceeded the maximum allowable values. With the exception of potato from irrigation site one, all vegetables exceeded the maximum permissible limit set for Fe concentration and out of which parsley, swiss chard, and green onion, all from site two, exceeded by more than double amount. The same trend is observed for the concentration of Mn and Fe in the soil samples. In fact, in both irrigation sites their concentration exceeded the allowable limits set by United Nation Environment Program (UNEP) for agricultural soils. The metal pollution load index revealed that in most of the vegetables studied the overall pollution load of trace metals were higher in Kolfe Keranyo irrigation site. The risk assessment study using indices like estimation of daily/weekly dietary exposure, hazard quotient and metal pollution load index all suggested consumption of the studied vegetables poses a significant health risk for the consumer. For adults the calculated target hazard quotient for the trace element Pb is higher than 1 (one) for all of studied vegetables ranging from 11.086 (cucumber) to 17.881 (beetroot) with a 98.216% and 98.464% contribution to the hazard indices, respectively. For a child consumer, Mn showed a higher target hazard quotient vales ranged from 0.0107 (cucumber) to 0.0495 (green onion) with a 70.86% and 88.85% contribution to the total hazard indices, respectively. The soil pollution indices also indicated that the degree of metal enrichment in soils and sediments are higher than the allowable limits. Therefore, a prompt action is required to curb the problem and ensure the public safety along the food system line.

Application of GIS and feedforward back-propagated ANN models for predicting the ecological and health risk of potentially toxic elements in soils in Northwestern Nigeria.

Potentially toxic elements (PTEs) occur naturally in most geologic materials. However, recent anthropogenic disturbances such as ore mining have contributed significantly to their enrichment in soils. Their occurrence in soil may portend a myriad of related risks to the environment and biota. Most traditional soil quality evaluation methods involve comparing the background values of the elements to the established guideline values, which is often time-consuming and fraught with computational errors. As a result, to conduct a comprehensive and unbiased evaluation of soil quality and its effects on the ecosystem and human health, this research combined geochemical, numerical, and GIS data for a composite health risk zonation of the entire study area. Furthermore, the multilayer perceptron artificial neural network (MLP-NN) was used to forecast the most important toxic components influencing soil quality. Geochemical, statistical, and quantitative soil pollution evaluation (pollution index and ecological risk index) showed that apart from mining, the spread and association of trace elements and oxides occur as a consequence of surface environmental conditions (e.g., leaching, weathering, and organo-metallic complexation). The hazard quotients (HQs) and hazard index (HI) of all PTEs were greater than one. This indicates that residents (particularly children) are more susceptible to risks from toxic element ingestion than dermal exposure and inhalation. Ingestion of As and Cr resulted in higher cancer risks and lifetime cancer risk levels (> 1.0E 04), with risk levels increasing toward the northeastern, western, and southeastern directions of the study area. The low modeling errors observed from the sum of square errors, relative errors, and coefficient of determination confirmed the efficiency of the MLP-NN in pollution load prediction. Based on the sensitivity analysis, Hg, Sr, Zn, Ba, As, and Zr showed the greatest influence on soil quality. Focus on remediation should therefore be placed on the removal of these elements from the soil.

Biological nitrogen fixation in rice paddy soils is driven by multiple edaphic factors and available phosphorus is the greatest contributor

Biological nitrogen fixation (BNF) is important for sustainable rice cultivation. Various edaphic factors have been individually evaluated for their effects on BNF in paddy soils. However, no single factor could fully explain the different soil outcomes. Paddy BNF is more likely to be simultaneously influenced to various degrees by combinations of several factors; however, the relative importance of the interaction of multiple edaphic factors on the regulation of BNF in rice soils is still unclear. Twenty-seven paddy soil samples with different soil properties were collected from major cropping areas in southwest and northeast China. Rice was transplanted into pots of these soils and grown in a 15N2 enriched airtight chamber. Estimation of BNF was based on measurements of 15N enrichment in the different soils and rice plants at the end of a 77-d incubation period. BNF amounts ranged from 0.66 to 12.3 kg ha−1. BNF had a significant positive relationship with available phosphorus (AP) and significant quadratic relationships with available molybdenum (AMo) and total soil nitrogen (TN). AP explained 42% of the observed variation in BNF, TN explained 17%, and AMo explained 13%. The specific interaction between the soil cation exchange capacity (CEC) and available soil N (ASN, as determined by rice N uptake) accounted for 28% of the variation. BNF was reduced when AP was < 14 mg kg−1, AMo < 0.09 mg kg−1, or when TN was > 3.2 g kg−1. These results provide valuable benchmarks that could be used to guide farmers in managing their soils to improve the potential contribution of paddy BNF to soil fertility.

ECOLOGICAL RISK ASSESSMENT OF HEAVY METALS ACCUMULATION IN SOIL AND ZYGOPHYLLUM ALBUM ALBUM: A CASE STUDY OF INDUSTRIAL PHOSPHATE VICINITY, TUNISIA

Contents and spatial distribution of heavy metals (Zn, Cu, Cd, Ni, As, Pb, Al and Ba) in the fine fraction of surface sediments and in Zygophyllum album shrub of zones influenced by phosphate industry in the region of Gabès, as well as in a control site (Sidi Ejjehmi) were determined. For the assessment of the level of sediment pollution, several parameters were calculated, including enrichment factor (EF), contamination factor (CF), Pollutant Load Index (PLI), Risk factor (Er), potential ecological Risk Index (Ri), Geoaccumulation Index (Igeo), Electrical Conductivity (Ec), Organic Matter (OM) and pH.Whereas, Bio-Concentration Factors (BCF) and Translocation Factors (TF) are calculated for the evaluation of pollution degree in Zygophyllum album. The soils of Gabès are characterized by a high average relative concentration of As, Ba, Cd, Cu, Ni, Pb, Al and Zn in all the study sites, indicating contributions from anthropogenic sources. The Igeo and the PLI of heavy metals show that all study sites are heavily polluted. All the EF values of all trace metals from Gabes sites (above 10), indicate a very significant enrichment in soils. The PCA, AC and correlation matrix suggest that soils are mainly polluted by As, Ba, Cd, Cu, Ni, Pb, Al and Zn. For all studied metals, the values of TF in Z. album from Gabes sites are greater than 1 except for Al at S2. All metals studied, except Cd, are more accumulated in shoots than in roots. Values of BAF are greater than 1, as well as TF values are greater than 1, so Z. album of Gabes can be considered as phytoremediator in the case of those studied metals. For Cd, TF is greater than 1 and BCF is less than 1, Z. album can be considered as a phytostabiliser for this metal.

Validating DayCent-CR for cropland soil carbon offset reporting at a national scale

Regenerative soil management practices have been shown to increase soil organic carbon in cropland previously under conventional management, and farmers that adopt regenerative practices could be eligible to participate in carbon offset programs. Due to the high cost of soil sampling at large scales, project developers of agricultural carbon offset programs may employ a hybrid measurement and modeling approach to SOC quantification. While biogeochemical models allow for carbon crediting to occur on larger scales than soil sampling alone would allow, any model used must be unbiased and shown to adequately predict SOC changes, with known uncertainty, across the crops, practice changes, and geographies of interest. The “credit-ready” version of the DayCent ecosystem model, DayCent-CR, was evaluated for performance across 14 combinations of crops and practice categories. Model calibration and validation was performed with a Bayesian Markov chain Monte Carlo approach using k-fold cross validation and 668 SOC stock change measurements from 41 agricultural research sites. Overall model performance met the guidelines established by Climate Action Reserve’s Soil Enrichment Protocol: ≥90% of model prediction intervals covered the measured value, and mean bias in all categories was less than pooled measurement uncertainty. Importantly, posterior distributions of DayCent-CR parameters and variance components enable the calculation of variance, which can then be used to calculate an uncertainty deduction that is applied to overall project credits to ensure conservatism. The calibrated model parameters are therefore valid for use in crediting programs within the domain of the validation dataset.

Spatial distribution and quantitative identification of contributions for nutrient and beneficial elements in top- and sub-soil of Huairou District of Beijing, China

To control agricultural and ecological risk, it is significant to monitor the quality of nutrient and beneficial elements (NBEs) in soils, particularly in agricultural area. For this purpose, it is important to clarify NBEs content and distribution, potential sources, and enrichment or depletion mechanism in soils. However, in present studies, the sources identification for soil NBEs and quantification of contributions for multiple sources, remains controversial. In order to solve these problems, in this case, a total of 977 topsoil samples and 258 subsoil samples were collected at Huairou District of Beijing. The content of some NBEs (K, Ca, Mg, V, Mn, F, Ge, N, Se, P, Zn, and S) were analyzed for each sample, and spatial distribution were presented with some values indicating soil properties (TFe2O3, Al2O3/SiO2, total organic carbon (TOC), and pH). The main influence factors of NBEs distibutions in soils were determined by the methods of principal component analysis (PCA), redundancy analysis (RDA), and positive matrix factorization (PMF) analysis. Combined with analysis result and geochemical process, it suggested the enrichment mechanism of NBEs in soils mainly impacted by soil parent material, the local external sources, and elements migration of eluviation in study area. Furthermore, the major contribittions of each NBEs either in topsoil or in subsoil were quantitatively determined. Generally both in topsoils and in subsoils, the source inherited from soil parent material account for 34.65–58.97% contribution to Zn, Mn, Mg, V, F, Ca, K, and Ge; the local external sources accounted 40.66–68.99% for N, S, Se, and Zn; and eluviation contributed 37.45–67.07% of Ca, P, and K. The enrichment degree of NBEs in topsoils were processed by standardized concentration ratio model, which effectively demonstrated elements inheritance from subsoils to topsoils. In addition, the soil quality evaluation was conducted on the basis of NBEs concentration classificaiton. This study quantitatively estimated NBEs sources in soils and their quality, which provided a basis for agricultural activities and ecological environment protection in typical suburban area.

A glimpse into the performance and synthesis of microbial nanoparticles and its new advances in soil enrichment and plant nutrition: a review

A glimpse into the performance and synthesis of microbial nanoparticles and its new advances in soil enrichment and plant nutrition: a review

Impaired Soil Health in Agricultural Areas Close to Fe-Ni Mines on Euboea Island, Greece, Caused by Increased Concentrations of Potentially Toxic Elements, and the Associated Impacts on Human Health

Agricultural soils close to mining establishments may suffer from airborne pollution, due to excavation and transportation activities. To assess the impact of soil pollution from potentially toxic elements (PTEs) on soil and human health in agricultural areas close to Fe-Ni mines, 36 composite topsoil samples were collected from central Euboea Island, Greece. The soils were analyzed for their physicochemical properties and for total and bioavailable Ni, Cr, Co, Mn, Fe, Pb, Cu, and Zn concentrations; the BCR sequential extraction protocol was additionally applied to all samples. Soil enrichment caused by the metals and the implications of soil degradation on the ecosystem were evaluated using the calculation of single pollution indices (PI) and the potential ecological risk index (RI), respectively. The hazard index (HI) for non-carcinogenic metals and life cancer risk (LCR) for carcinogenic metals were used to appraise the human health risks. Extremely high, very high, and considerably high total concentrations of Ni, Cr, and Mn, respectively, were determined. Though most of the total amounts of metals in soil samples were found to be related to the residual fraction, the considerable portion extracted in the first two steps of the BCR process can be regarded as able to introduce toxicity issues in the local biota. High PI values of Cr, Co, and especially Ni point to severely polluted soils, and the mean RI values indicate a considerable risk for biota. HI values &gt; 1 show increased possibilities for non-carcinogenic health issues in children, whereas the LCR values of Ni were above the critical limit, 1 × 10−4, for both children and adults.

Isolation and Identification of β-Glucosidases-Producing Non-Saccharomyces Yeast Strains and Its Influence on the Aroma of Fermented Mango Juice.

The cultivation and enrichment of different soils in a vineyard yielded 95 yeast species. Among them, seven strains capable of producing β-glucosidases were identified using the aescin colorimetric method. One non-Saccharomyces yeast strain was isolated from a plate containing lysine and identified using internal transcription (ITS) as Candida cf. sorbosivorans (C. cf. sorbosivorans), which was named Candida cf. sorbosivorans X1. Additionally, the enzymatic characteristics of the β-glucosidases produced by this strain were investigated. The β-glucosidases generated by C. cf. sorbosivorans X1 displayed high enzymatic activity and enzyme-activity retention in a pH range of 3.0 to 5.4 and at temperatures of 30 °C to 35 °C. Using non-targeted metabolomics methods, we investigated the alterations in metabolites during the fermentation of mango juice. The strain C. cf. sorbosivorans X1 demonstrated activity against phenols and terpenes. In the fermented mango juice (X1FMJ), we identified 41 differential metabolites. These included 14 esters, 4 hydrocarbons, 3 aldehydes, 5 ketones, 4 terpenoids, 4 alcohols, 1 aromatic hydrocarbon, 2 amines, 1 acid, and 3 heterocyclic compounds. The metabolic pathways of these differential metabolites were analyzed, revealing four key pathways: tyrosine metabolism, phenylpropanoid biosynthesis, monoterpene biosynthesis, and α-linolenic acid metabolism, which promoted the formation of aroma compounds in the fermented mango juice.

Mung Bean Nutrient Uptake and Root Response to Phosphorus and Potassium Placement Strategies

ABSTRACT A pot experiment was conducted to examine the effect of co-application of phosphorus (P) and/or potassium (K) fertilizer to a soil layer on Mung bean (Vigna radiata R. Wilczek) grown in a Yellow Chromosol soil. We hypothesized that adding K to a P- enriched soil layer would increase recovery of K due to increased root proliferation. Layers enriched with P, K or a combination of P and K were placed at either 5 or 20 cm depth in 50 cm deep pots, and a uniform PK application treatment included for comparison. Mung bean was grown for 45 days and key growth and nutrient uptake attributes were assessed. Phosphorus application increased shoot and root dry matter yield and shoot yield was 40% higher in the shallow P treatment and 77% higher in the shallow PK than in the uniform PK treatment. Shallow co-application of P and K increased shoot P and K content compared with shallow P alone. Apparent P fertilizer recovery (%PAFR) followed the same pattern, and there was an 8 to 12-fold increase in %KAFR. There was no evidence of an increase in either the proportion or mass density of roots in the enriched soil layers in any treatment. P and K fertilizer use efficiency was maximized by co-application in an enriched soil layer. When multiple nutrient deficiencies occur co-application of nutrients in a soil layer accessible to roots maximizes fertilizer use efficiency.

Effect of stabilization time and soil chromium concentration on Sesbania virgata growth and metal tolerance

Sesbania virgata is a pioneer shrub from the Fabaceae family, native to riparian environments in northeast of Argentina, southern of Brazil and Uruguay. In peri-urban riparian soils, metal contamination is a frequent problem, being its bioavailability partly determined by the stabilization time and frequency of contamination events. The effect of time elapsed between chromium (Cr) soil enrichment and plant seeding and Cr doses on S. virgata tolerance and metal absorption were evaluated. Treatments were developed by adding Cr (80–400 ppm) to the soil and allowing two days or fifteen months to elapse before sowing, and a control treatment without Cr addition. After 150 days from seeding, bioaccumulation and translocation factors, growth parameters (dry biomass and its aerial/radical allocation pattern, stem length and its elongation rate), morphological parameters (root volume and leaf area), and physiological parameters (chlorophyll content) of the specimens were determined. The emergence of S. virgata was inhibited since 150 ppm when Cr was added to the soil two days before seeding, with Cr accumulation in roots starting at 80 ppm (17.4 ± 2.5 mg kg−1). Under 15 months of metal stabilization, S. virgata plants survived across the entire range of Cr doses tested, with accumulation in roots since 100 ppm (35.5 ± 0.2 mg kg−1) and metal translocation to aerial tissues only under 400 ppm. The results obtained showed that S. virgata did not have high BCF and TF values, suggesting that it cannot be classified as bioaccumulator of Cr under the tested conditions. However, its presence in environments contaminated with Cr can be beneficial, as it helps to stabilize the metal in the soil.

Dietary sources apportionment and health risk assessment for trace elements among residents of the Tethys-Himalayan tectonic domain in Tibet, China.

Dietary intake of toxic elements (TEs) and essential trace elements (ETEs) can significantly impact human health. This study collected 302 samples, including 78 food, 104 drinking water, 73 cultivated topsoil, and 47 sedimentary rock from a typical area of Tethys-Himalaya tectonic domain. These samples were used to calculate the average daily dose of oral intake (ADDoral) and assess the health risks of five TEs and five ETEs. The results indicate that grain and meat are the primary dietary sources of TEs and ETEs for local residents. The intake of manganese (Mn) and copper (Cu) is mainly from local highland barley (66.90% and 60.32%, respectively), iron (Fe) is primarily from local grains (75.51%), and zinc (Zn) is mainly from local yak meat (60.03%). The ADDoral of arsenic (As), Mn, Fe and Zn were found to be higher than the maximum oral reference dose in all townships of study area, indicating non-carcinogenic health risks for local residents. Additionally, lead (Pb) and nickel (Ni) in 36.36% townships, and Cu in 81.82% townships were above the maximum oral reference dose, while As posed a carcinogenic risk throughout the study area. The concentrations of As, mercury (Hg), Pb, Mn, Cu Fe and selenium (Se) in grains were significantly correlated with those in soils. Moreover, the average concentrations of As in Proterozoic, Triassic, Jurassic and Cretaceous was 43.09, 12.41, 15.86 and 6.22 times higher than those in the South Tibet shell, respectively. The high concentrations of TEs and ETEs in the stratum can lead to their enrichment in soils, which, in turn, can result in excessive intake by local residents through the food chain and biogeochemical cycles . To avoid the occurrence of some diseases caused by dietary intake, it is necessary to consume a variety of exotic foods, such as high-selenium foods, foreign rice and flour in order to improve the dietary structure.

Utilization of fly ash and bottom ash waste: a study at PLTU Tanjung Jati B, Jepara, Indonesia

The high energy needs force the massive use of coal. PLTU as one of the largest energy-producing industries currently has a significant impact on the environment and social economy. One of the wastes from PLTU activities is fly ash and bottom ash (FABA). By taking a research study at the Tanjung Jati B PLTU one of the largest PLTUs in Indonesia, the authors try to see the impact of FABA waste on the environment and analyze the potential that can be utilized. The research approach used is quantitative by collecting data through literature studies. The results showed that FABA had a negative impact on the environment, especially when it was only left buried in landfills. On the other hand, FABA has the potential to improve the economy, especially for the people around the PLTU industry, including in the agricultural aspect. One of the benefits of FABA is for building construction purposes with a mixture of 20% to 35%. For agriculture, FABA is proven for soil enrichment on a small scale with a mixture of 35% to 50% and can increase the nutrients in the soil .

Effect of Environmental, Soil and Management Factors on Weed Flora of Field Pea in South-East Hungary

Pea is a widely cultivated leguminous plant which also contributes to soil enrichment through nitrogen fixation and benefits crop rotations. However, large weed populations are a challenge for pea production, requiring effective management strategies. It is essential to highlight the influence of soil parameters, factors affecting the environment, and management practices on weed populations to develop effective weed control and maximize pea yield and ease of harvesting. In our study, a total of 31 pea fields were surveyed prior to harvest to determine the coverage of each weed species, with the aim of identifying the typical weeds in the study area. In addition, environmental, soil, and management factors were recorded for each field. Based on our hypotheses, these factors influence the weed composition, and these effects can be described by the dominance of weed species. In our study, summer annuals and geophytic perennials were common, with Echinochloa crus-galli and Convolvulus arvensis being most dominant. The analysis revealed that the year of data record, soil type, and farming system most significantly influenced weed composition. Weed species were observed to have varying responses to soil texture, salt concentration, and phosphorus content. The survey period, geographical factors, farming system, and tillage practices also played a role in determining weed flora. The findings suggest strong correlations between soil parameters and weed composition, highlighting the importance of soil management in weed control. The year of data collection had the greatest influence on weed infestation. Soil-related variables, such as soil type, also played a significant role. Farming systems had a smaller effect on weed composition. Comparing our results with previous country level weed surveys in Hungary, our results identified some unique characteristics in the weed flora of South-East Hungary.

Hyphosphere microorganisms facilitate hyphal spreading and root colonization of plant symbiotic fungus in ammonium-enriched soil.

Anthropogenic nitrogen inputs lead to a high ammonium (NH4+)/nitrate (NO3-) ratio in the soil, which restricts hyphal spreading of soil fungi. Access of symbiotic fungi to roots is a prerequisite for plant-fungal interactions. Hyphosphere bacteria protect fungi from environmental stress, yet the impact of hyphosphere bacteria on adaptation of host fungi to NH4+-enriched conditions remains unclear. By developing soil microcosm assays, we report that a plant-symbiotic fungus, Phomopsis liquidambaris, harbors specific hyphosphere bacteria that facilitate hyphal spreading and assist in the root colonization in NH4+-enriched soil. Genetic manipulation, 16S rRNA gene analysis and coinoculation assays revealed that the genus Enterobacter was enriched in the hyphosphere of NH4+-sensitive wild-type compared to NH4+-preferring nitrite reductase-deficient strain. The representative Enterobacter sp. SZ2-promoted hyphal spreading is only evident in nonsterilized soil. We further identified an increased abundance and diversity of ammonia-oxidizing archaea (AOA) and a synchronously decreased NH4+:NO3- ratio following SZ2 inoculation. Microbial supplementation and inhibitor assays showed that AOA-mediated reduction in NH4+:NO3- ratio is responsible for SZ2-enhanced fungal adaptation to NH4+-enriched conditions. The Ph. liquidambaris-Enterobacter-AOA triple interaction promoted rice growth in NH4+-enriched soil. Our study reveals the essential role of hyphosphere microorganism-based hyphal spreading in plant-fungal symbiosis establishment within nitrogen-affected agroecosystems.

Pembuatan Pupuk Kompos Dari Kotoran Kambing

Organic fertilizers are fertilizers derived from various natural fertilizer-making materials such as animal manure, animal body parts, plants, which are rich in minerals and good for the use of soil enrichment. The purpose of writing this journalistofind out how to make compost from goat manure. The research method used is library research by collecting various information from journals, books and others. The results showed that the manufacture of organic fertilizer from goat manure has always been a product that is often used by farmers, because it has nutrients, rich minerals for plant fertilizer and growth and is safe for the health of farmers, because it is free from harmful chemicals.&#x0D; Keywords: Compost, Goat Manure.

Principal Component Analysis to Assess the Heavy Metal Enrichment in the Urban Soils of Kabini Basin: Emerging Concerns

Heavy metal enrichment in urban soils demarcates a major ecological concern. The emerging industries, settlements and agricultural lands in bank of Kabini River resulted in prominent changes in water and soil geochemistry. In present work, a total of 20 soil samples from Kabini Basin have been checked for trace metals concentration and assessed following multivariate statistical approach. The PCA has been conducted to characterize the trace metals as per the common source of origin. The factors distinguished the heavy metals into 3 components with overall variance of 82.53%. Higher loading of various heavy metals indicates natural and anthropogenic interferences in soil. The baseline data generated from the present study provides the insight over the concentration of heavy metals, which would further be helpful in conservation and management of soil resources of the basin. Keywords: Heavy Metal, PCA, Urban Soils, Kabini Basin