Organic Sources Research Articles

The use of organic calcium derived from eggshell waste on physiological and intestinal conditions of broiler chickens

The study aimed to investigate the effect of using eggshell waste or eggshell extract as organic calcium source in feed on the physiological conditions and intestines of broilers. A total of 392 one-day-old chicks were randomly distributed into four groups (10 birds each group), CONT (control diet con taining 1% limestone as an inorganic calcium source), EGFL (feed containing 1% eggshell powder as an organic calcium source), EEG1 (feed containing 1% eggshell extracted with Averrhoa bilimbi L. fruit filtrate as an organic calcium source), and EEG05 (feed containing 0.5% eggshell extracted using A. bilimbi L. fruit filtrate). Body weight and feed intake were recorded weekly, whereas blood, intesti nal content, and small intestinal segments were collected at day 35. Our results showed that during days 8-35, weight gain and feed consumption were lower (P<0.05) in EEG05 than in CONT and EGFL. Thymus relative weight tended (P=0.08) to be lower in EEG05 than in CONT, and gizzard was lower (P<0.05) in EGFL than in CONT and EEG05. Serum total triglyceride was significantly higher in CONT than in other groups. Moreover, serum high-density lipoprotein was higher in EEG1 and EE G05 than in CONT (P<0.05). furthermore, serum albumin were higher (P<0.05) in EEG1 than in CONT, EGFL and EEG05. Additionally, serum uric acid was higher (P<0.05) in EEG1 than in EGFL and EEG05. Among the groups, SGPT levels were lowest (P<0.05) in EEG05 birds. While there was no effect (P>0.05) of treatments on coliform and lactic acid bacteria in the ileum and caecum, jejunal crypt depth tended (P=0.09) to be lower in EEG1 and EEG05 than in CONT and EGFL broilers. Con clusively, using 1% eggshell powder or eggshell extract in feed as the substitute for limestone had no detrimental effect on broiler chickens’ growth, physiological status and intestinal condition. Hence, eggshell powder or eggshell extracted with A. bilimbi L. fruit filtrate can be used as an organic calcium source to replace limestone.

Effects of Different Sources of Fertilizers on Growth and Yield of Radish (Raphanus sativus L.)

Radish is a widely cultivated root crop susceptible to chemicals for its growth and development. The experiment was conducted to study the effect of different sources of organic fertilizers on growth and yield parameters in the Tokinashi variety of radish. The experiment was laid out using one factorial completely randomized block design with six treatments replicated four times. Vermicompost, goat manure, chemical fertilizers (NPK), poultry manure, farmyard manure and control were the applied treatments. Various growth and yield parameters of radish were measured and assessed at 15-day intervals. Various growth and yield parameters of radish were measured and assessed at 15-day intervals. Growth parameters were observed at 15, 30, 45, and 60 days after sowing. For yield parameters, destructive samples were taken and observed at 30 DAS and 45 DAS and harvested at 60 DAS. The assessments of plant growth and yield parameters showed that poultry manure (PM) treatments were superior. At the time of harvesting, the treatment comprising poultry manure had considerably greater plant height (30.55 cm), leaf length (29.44cm), leaf breadth (10.78cm), leaf number per plant (9.23), root diameter (10.33cm) and root length (20.16cm) with superior yield per ha (33.59 mt ha-1). Poultry manure significantly enhanced root yield and was positively correlated with all growth parameters. The highest benefit-cost (B: C) ratio was recorded in chemical fertilizer (3.99), which was statistically at par with poultry manure (3.81), suggesting that poultry manure might potentially replace chemical fertilizers for the Tokinashi variety of radish cultivation.

Structure, acquisition, assembly, and function of the root-associated microbiomes in Japonica rice and hybrid rice

Understanding the genetic and environmental factors that structure root-associated microbiomes is necessary to inform rice (Oryza sativa L.) breeding and fertilizer. Herein, we comprehensivly explored the microbiomes along four fine-scale root compartments, bulk soil, rhizosphere, rhizoplane and endosphere, between traditional Japonica rice and improved hybrid rice acorss three spatially distant locations. Bacterial diversity decreased monotonically from external bulk soil to internal endosphere. The acquisition of endosphere symbionts is governed conjointly by a two-step selection process and an amplification selection process, which depends on the bacterial functional group. The bacterial communities are primarly affected by root compartment and planting location, followed by relatively samll but signifcant rice genotype effect. The exterior bulk soil, rhizosphere and rhizoplane communities are govrned by variable selection. In contrast, the internal endosphere counterparts are shapped by homogenizing selection, which are undiscernible between the two rice genotypes. After ruling out planting location effect, we screened 12 rice genotype-discriminatory orders that contributed an overall 97.22 % accuracy in diagnosing rice genotype. Hybrid rice is inferior to Japonica rice in carbon and nitrogen fixation, nitrogen and phosphorus biomineralization from organic sources. Collectively, we proposed a conceptual model to infer rice genotype effect on the rhizosphere microbiomes, and the subsequent requirement of external fertilizer for sustaining yield. Our findings deepen our understanding of the complex rice genotype–root microbiomes–fertilizer interactions from the prespective of microbially-mediated nutrient cycles.

Real-time diagnosis and monitoring of biofilm and corrosion layer formation on different water pipe materials using non-invasive imaging methods

Water distribution networks play a crucial role in ensuring a reliable water supply, yet they encounter challenges such as corrosion, scale formation, and biofilm growth due to interactions with environmental elements. Biofilms and corrosion layers are significant contaminants in water pipes, formed by complex interactions with pipe materials. As the structure of these contamination layers varies depending on the pipe material, it is essential to investigate the contamination layer for each material individually. Specifically, biofilm growth is typically investigated concerning organic sources, while the growth of humus layers is examined in relation to inorganic elements such as manganese (Mn), iron (Fe), and aluminum (Al), which are major elements and organic substances found in water pipes. Real-time imaging of recently contaminated layers can provide important insights to improve system performance by optimizing operations and cleaning processes. In this study, cast iron (7.10 ± 0.78 nm) exhibits greater surface roughness compared to PVC (5.60 ± 0.14 nm) and provides favorable conditions for biofilm formation due to its positive charge. Over a period of 425 h, the fouling layer on cast iron and PVC surfaces gradually increased in fouling thickness, porosity, roughness, and density, reaching maximum value of 29.72 ± 3.6 μm, 11.44 ± 1.1%, 41673 ± 1025.6 pixels, and 0.80 ± 0.3 fouling layer pixel/layer pixel for cast iron, and 8.15 ± 0.4 μm, 20.64 ± 0.9%, 35916.6 ± 755.7 pixels, and 0.58 ± 0.1 fouling layer pixel/layer pixel, respectively. Within the scope of the current research, CNN model demonstrates high correlation coefficients (0.98 and 0.91) in predicting biofilm thickness for cast iron and PVC. The model also presented high accuracy in predicting porosity for both materials (over 0.91 for cast iron and 0.96 for PVC). While the model accurately predicted biofilm roughness and density for cast iron (correlation coefficients 0.98 and 0.94, respectively), it had lower accuracy for PVC (correlation coefficients 0.92 for both parameters).

Electrochemical Enrichment of Biocharcoal Modified on Carbon Electrodes for the Detection of Nitrite and Paraxon Ethyl Pesticide

Biocharcoal (BioC), a cost-effective, eco-friendly, and sustainable material can be derived from various organic sources including agricultural waste. However, to date, complex chemical treatments using harsh solvents or physical processes at elevated temperatures have been used to activate and enhance the functional groups of biochar. In this paper, we propose a novel easy and cost-effective activation method based on electrochemical cycling in buffer solutions to enhance the electrochemical performance of biocharcoal derived from almond shells (AS-BioC). The novel electrochemical activation method enhanced the functional groups and porosity on the surface of AS-BioC, as confirmed by microscopic, spectroscopic characterizations. Electrochemical characterization indicated an increase in the conductivity and surface area. A modified SPCE with activated AS-BioC (A.AS-BioC/SPCE), shows enhanced electrochemical performance towards oxidation and reduction of nitrite and paraxon ethyl pesticide, respectively. For both target analytes, the activated electrode demonstrates high electrocatalytic activity and achieves a very LOD of 0.38 µM for nitrite and 1.35 nM for ethyl paraxon with a broad linear range. The sensor was validated in real samples for both contaminants. Overall, the research demonstrates an innovative technique to improve the performance of AS-BioC to use as a modifier material for electrochemical sensors.

Effect of dietary protein reduction on growth performance and water quality of the blue streak hap Labidochromis caeruleus (Fryer, 1956) reared in a biofloc system

The 8-week study evaluated the effect of dietary protein reduction on growth performance and water quality of blue streak hap (Labidochromis caeruleus) using biofloc technology (BFT). Fish averaging 0.67 ± 0.13 g in weight were distributed into 15 polyester tanks, each with a water volume of 60 L within 100 L tanks, accommodating 15 fish per tank. Four isolipidic and isoenergetic diets were formulated with gradually decreasing protein levels (40%, 35%, 30%, and 25%). Four biofloc groups (40P + BF, 35P + BF, 30P + BF, and 25P + BF) and control (C) (40P + without BF) were fed twice daily (09:00 and 17:00) at a rate of 5% of their body weight. Molasses was added to the experimental tanks on a daily basis as an organic carbon source. This ensured that the biofloc tanks had a balanced carbon/nitrogen (C/N) ratio and facilitated control of total ammonia nitrogen (TAN), nitrite-nitrogen (NO2-N), and nitrate-nitrogen (NO3-N) levels. The nutritional composition of the bioflocs obtained from the experimental groups revealed that the crude protein and crude lipid contents were 37.00–38.14% and 1.45–1.52%, respectively (P > 0.05). The best specific growth rate (SGR) (1.68%) and feed conversation ratio (FCR) (2.21) were determined in the 35P group. Based on the overall evaluation of the study’s data, it can be concluded that the dietary protein for the blue streak hap (L. caeruleus) can be reduced from 40 to 35% in a biofloc system without any negative effects on health. Improving water quality and providing additional food to fish through zero water exchange and organic carbon addition (BFT) can be considered a sustainable aquaculture technique that can be used in ornamental fish farming.

Effect of inorganic and organic nitrogenous sources on soil fertility, nutrient uptake and economics of paddy (Oryza sativa) crop in Indo-Gangetic plains

Effect of inorganic and organic nitrogenous sources on soil fertility, nutrient uptake and economics of paddy (Oryza sativa) crop in Indo-Gangetic plains

Performance evaluation of typical flocculants for efficient harvesting of Chlorella sorokiniana under different carbon application modes

In this study, the growth characteristics of microalgae cultured with different carbon sources were analyzed, and the flocculation characteristics under the influence of carbon sources were evaluated using three typical flocculants. The results showed that the organic carbon sources could significantly increase the content of extracellular proteins in microalgae. Specifically, the extracellular protein concentrations of microalgae cultured with pure BG-11, ethanol, sodium acetate and glucose were 18.2 29.2, 97.3, and 34.7 mg/g, respectively. During the flocculation process, microalgae cultured with sodium acetate exhibited a weak response to the flocculant because of excessive extracellular proteins inhibited flocculation. In addition, the flocculation efficiency was also less than 50.0% cultured with sodium acetate in all pH test ranges when alum and chitosan were used as flocculants. It could be inferred that the flocculant initially happened to charge neutralization with the negatively charged proteins in the solution and then bridged the charges with the microalgae. These findings provide insights into the effects of different carbon sources on microalgal flocculation, promising organic integration of microalgae wastewater treatment and harvesting.

Organic nano carbon source inducing 3D silica nanoparticles-graphene nanosheet layer on Cu current collector for high-performance anode-free lithium metal batteries

Anode-free lithium metal batteries (AFLBs) have attracted considerable attention due to their high theoretical specific capacity and absence of Li. However, the heterogeneous Li deposition and stripping on the lithiophobic Cu collector hamper AFLBs in practice. To achieve a uniform and reversible Li deposition, a carbon-based layer on the Cu collector has attracted intense interest due to its high conductivity. However, the 2D single-component carbon-based interface is inadequate lithiophilic for obtaining the homogeneous Li deposition and preventing the lithium dendrite from piercing the separator. Herein, we present a 3D embedded lithiophilic SiO2 nanoparticles-graphene nanosheet matrix (SiO2@G-M) on the Cu collector by organic nano carbon source. In this structure, the lithiophilic SiO2 nanoparticles as active points promote the homogeneous lithium nucleation and the 3D graphene nanosheet matrix offers homogenous electron distribution and voids to prevent the piercing. Finally, SiO2@G-M/Li cell shows a high coulombic efficiency of 98.62 % after 100 cycles at a high current density of 2 mA cm−2 with an areal capacity of 1 mAh cm−2.

Exploring the effects of varying levels of selenium-chitosan on production performance, egg quality, and immune health in laying japanese quail

The purpose of this research was to see how different levels of Se-chitosan, a novel organic source of Se, affected the production performance, egg quality, egg Se concentration, microbial population, immunological response, antioxidant status, and yolk fatty acid profile of laying Japanese quail. This experiment used a totally randomized design, with 5 treatments, 6 repeats, and 10 birds in each repetition. The dietary treatment groups were as follows: no Se supplementation (control group), 0.2 mg/kg Na-selenite supplementation, and 0.2, 0.4, and 0.6 mg/kg Se-chitosan supplementation. The feed conversion ratio (FCR) improved linearly in quails fed different levels of Se-chitosan compared to the control group (P < 0.05). Furthermore, Se-chitosan at concentrations of 0.2 and 0.4 mg/kg demonstrated both linear and quadratic increases in albumen height, Haugh unit, and yolk color in fresh eggs compared to the control group. Additionally, Se-chitosan contributed to enhanced shell thickness and strength, along with an increased Se concentration in the yolk. Se-chitosan supplementation at different levels linearly and quadratically reduced coliforms (COL) while increasing lactic acid bacteria (LAB)/coliform ratios (P < 0.05). Se-chitosan supplementation linearly and quadratically increased the total antibody response to sheep red blood cells (SRBC) and IgG titers (P < 0.05). It also linearly decreased the level of malondialdehyde in fresh and stored egg yolks and increased the activity of antioxidant enzymes catalase and glutathione peroxidase linearly, and superoxide dismutase (SOD) both linearly and quadratically in quail blood serum (P < 0.05). Additionally, supplementation of Se-chitosan at levels of 0.2 and 0.6 mg/kg linearly decreased the ∑ n-6 PUFA/∑ n-3 PUFA ratio in the yolk compared to the control group (P < 0.05). It can be concluded that incorporating Se-chitosan as a novel organic source of Se in the diet of laying quails can enhance production performance, egg quality, egg Se concentration, yolk lipid oxidation, microbial population, immune response, antioxidant enzyme activity, and yolk fatty acid profile.

Optimizing Growth and Yield in Aerobic Rice through IoT-based Drip Irrigation and Fertigation

Aim: A field experiment was conducted to study the effect of different IoT based drip irrigation and fertigation management practices on growth and yield of aerobic rice. Study Design: The experiment was laid out in a strip plot design with 4 main plots (Horizontal) and 3 sub-plots (Vertical) that are allocated randomly and replicated thrice. Place and Duration of Study: kharif and rabi seasons of 2022-23 &amp; 2023-24 at ICAR-Indian Institute of Rice Research, Hyderabad. Methodology: The horizontal plot treatments were Nitrogen management practices (4) i.e., Control (N1), 100 % RDN (100% inorganic) (N2), 100 % RDN (50% inorganic &amp; 50% organic) (N3) and 125 % RDN (100 % inorganic) (N4). Vertical plots treatments were Irrigation management practices (3) which include Saturation (I1), 10 % DASM (I2) and 20 % DASM (I3). Organic nutrient sources were given as soil application and the inorganic sources were applied through fertigation. Sensor based (IoT) irrigation scheduling was done. Results: Nitrogen application of 125% RDN with 100% inorganic consistently resulted in higher growth parameters (plant height (110.4 cm and 93.9 cm), number of tillers m-2 (392.2 and 291.8) and plant dry weight (11814.8 kg ha-1 and 9557.0 kg ha-1) during kharif &amp; rabi respectively) followed by 100% RDN (100% inorganic) and 100% RDN (50% inorganic &amp; 50% organic) in pooled data. Saturation irrigation resulted in taller plants with greater growth parameters (plant height (109.8 cm and 91.0 cm), number of tillers m-2 (412.3 and 283.6) and plant dry weight (10916.0 kg ha-1 and 9463.4 kg ha-1) during kharif &amp; rabi respectively) compared to deficit irrigation treatments. Treatment of 125% RDN with 100% inorganic resulted in the higher yield attributes (no. of panicles m-2 (154.3 and 141.1), no. of filled grains panicle-1 (142.3 and 124.0), panicle weight (3.1 g and 3.3 g) during kharif &amp; rabi respectively) and yield (4790.2 kg ha-1 and 4583.8 kg ha-1) which was statistically similar with 100% RDN (100% inorganic) and 100% RDN (50% inorganic &amp; 50% organic). Saturation expressed higher yield attributes (no. of panicles m-2 (149.5 and 139.2), no. of filled grains panicle-1 (135.0 and 121.6), panicle weight (3.0 g and 3.2 g) during kharif &amp; rabi respectively) and yield (4554.0 kg ha-1 and 4425.5 kg ha-1) which was on par with 10% DASM. The interaction was found to be non-significant. Conclusion: Nitrogen application of 125% RDN and 100% RDN through fertigation were found to have statistically similar growth, yield parameters and yield. IoT based irrigation at 10% DASM was found to be on par with saturation treatment among all the growth, yield parameters and yield of aerobic rice.

Molecular organic geochemistry and origin of oil in the Potwar Basin, Pakistan

The Potwar Basin (PTB) is a prominent geological feature located in northern part of Pakistan, and is considered as one of the active and productive regions for petroleum and gas exploration in Pakistan. In this study, eight crude oil specimens originating from three distinct fields within the PTB were comprehensively examined to decipher the environmental conditions, source of organic matter (OM) and oil-oil correlations using gas chromatography coupled with flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC–MS). The molecular marker and hierarchical cluster analysis of PTB oils reveal two different crude oil families. Family-I showed relatively low values of Pr/Ph, C19TT/C23TT and C25TT/C24TeT, C27-C29 regular steranes, dibenzothiophene (DBT), fluorene (FL) and dibenzofuran (DBF), as well as C26/C28 TAS (20S) and C27/C28 TAS (20R). These results suggest that Family-I crude oils derived from marine environment of suboxic water bodies with higher contribution from green algae or planktonic microbes. However, Family II contains comparatively high values of the aforementioned molecular parameters, indicating that crude oils mainly originated from a lacustrine environment with a higher contribution of plant organisms under oxidizing conditions. Saturated hydrocarbon maturity parameters such as CPI and OEP, and C3122S/(C3122S + C3122R) and C3222S/(C3222S + C3222R) indicate PTB crude oils are thermally mature, while aromatic indices reveal that Family-II crude oils are high mature. The present research defines that PTB crude oils contributed from mixed organic matter sources of marine and lacustrine majorly from marine sedimentary environment with the bloom of algae and/or higher plants.

Sustainable Methods for Growing Turmeric: Evaluating the Effects of Synthetic and Organic Fertilizers on vegetative and reproductive attributes

This study aimed to assess the influence of various bio-fertilizer sources on turmeric (Curcuma longa L.) cultivation in Eastern Nepal. The research was conducted at G.P Koirala College of Agriculture and Research Centre, Sundarharaicha, Morang, Nepal, from April 2023 to January 2024. The experiment utilized a randomized complete block design (RCBD) with seven treatments including T1: Recommended dose (RD) of NPK, T2: Goat manure, T3: Organic manure, T4: Poultry manure, T5: Vermicompost, T6: Farmyard manure, T7: Control, replicated three times. Turmeric cultivation practices were implemented following standard agronomic procedures. The recommended dose of synthetic fertilizer, NPK, exhibited the highest enhancement across multiple vegetative and reproductive growth parameters of turmeric, with notable increases in plant height, leaf number, tillers per plant, primary and secondary fingers per clump, fresh rhizome yield, dry yield, and dry recovery percentage. Among the organic sources, goat manure and poultry manure also showed promising results in enhancing turmeric yield and quality. Specifically, NPK recorded the highest fresh rhizome yield at 21.30 tons/ha, while goat manure and poultry manure yielded 20.35 tons/ha and 18.69 tons/ha, respectively. In contrast, the lowest fresh rhizome yield was observed in the control group, indicating minimal enhancement in yield without fertilizer supplementation. The results highlight how organic farming methods may be a good substitute for traditional chemical fertilizers in the context of sustainable turmeric production.

Peritoneal dialysis-associated peritonitis, caused by superior mesenteric artery thrombosis with intestinal necrosis: a case report.

Peritoneal dialysis (PD)-associated peritonitis is a common complication of PD. Enteric peritonitis is defined as peritonitis arising from an intestinal or intra-abdominal organ source. The delay in the diagnosis or treatment of enteric peritonitis has been reported to increase mortality. Therefore, the early consideration of enteric peritonitis, particularly in cases of culture-negative peritonitis, is imperative. A 67-year-old Japanese man who had been undergoing PD for 3years, was admitted to our hospital with a diagnosis of PD-associated peritonitis. A month previously, he experienced a bleeding gastric ulcer, which led to severe anemia (hemoglobin 6.3mg/dL), followed by thrombocytosis. On admission, peritoneal fluid analysis showed a high white blood cell count (WBC: 8,570 /µL), with neutrophils predominating (74.5%). Cultures of both his dialysis effluent and blood were negative. After admission, the WBC count of the dialysis effluent gradually decreased alongside antibiotic therapy, but the patient's abdominal pain did not improve. After 4days, enhanced computed tomography showed superior mesenteric artery (SMA) thrombosis and intestinal necrosis. Therefore, emergency intestinal resection and PD catheter removal were performed, and then antithrombosis therapy was initiated. Because the patient's abdominal pain was improved and platelet count and D-dimer concentration were reduced by these treatments, he was discharged from the hospital after 47days. Thus, we report a rare case of culture-negative PD-associated peritonitis, which was caused by SMA thrombosis and intestinal necrosis. It is likely that combination of severe calcification of SMA and prolonged thrombocytosis secondary to the severe anemia contributed to the thrombosis.

English

In modern agriculture, soil salinity stress has been extensively studied by researchers owing to its disastrous impacts on soil and plant health. Zinc (Zn) is an essential micronutrient. Crucial role of Zn in regulating plant growth under salinity stress has been well documented. Current research consisted of two studies, first study was aimed at comparing three organic (i.e. sugarcane filter cake, farmyard manure and poultry manure) and inorganic sources (i.e. zinc oxide, zinc sulphate and zinc nitrate) of Zn for improving Zn uptake by salt tolerant wheat varieties in a pot trial. Whereas, in second experiment the effect of zinc sulfate (ZnSO4; inorganic) alone and in combination with sugarcane filter cake (SFC; organic) was evaluated in sustaining wheat growth under naturally salt affected soil. Results from pot trial suggested that among different organic sources, SFC application significantly enhanced the plant height (12.52%), spike length (9.07%) and number of fertile tillers (25%), whereas, application of ZnSO4 among the inorganic sources resulted in notable enhancements in plant height (7%), number of fertile tillers (24%), and spike length (8%) compared to their corresponding treatments. In addition, wheat variety Sehar-2006 proved to be the most efficient wheat variety under salinized conditions. Whereas the findings of the field trial revealed ZnSO4 application @ 24 kg ha-1 in combination with SFC 1 % w/w improved the plant height (2%), grain yield (81%), K+/Na+ ratio (1.4 fold), catalase (8%) and peroxidase (3%) activities.

Effect of different organic sources and time of manuring on the growth, yield and quality of cabbage (Brassica oleracea var. capitata)

A field experiment was conducted during the rabi season of 2022-2023 at the Instructional cum Experimental Farm, Nagaland University, School of Agricultural Sciences, Medziphema campus to evaluate the “Effect of different organic sources and time of manuring on the growth, yield and quality of cabbage (Brassica oleracaea var. capitata). The experiment consisted of 15 treatments laid out in RBD with three replications. Result of the experiment clearly revealed that application of 75% N through VC one day before transplanting + 25% N through VC 20 DAT obtained maximum growth parameters, quality parameters and yield parameters with plant height (29.69 cm), stem diameter (2.73 cm), plant spread (50.37 cm), head compactness (34.70 cm), ascorbic acid content (9.16 mg 100-1g) and protein content (2.53%), head diameter (13.48 cm), head size (152.41 cm2), gross head weight (1416.67 g), net head weight (865.03 g), yield per plot (10.36 kg) and projected yield per hectare (24.03 t). Highest available N (301.66 kg ha-1) was recorded in T15 (RDF) while T4 (100% N through FYM 10 days before transplanting) recorded the maximum available phosphorous (49.45 kg ha-1). Maximum available potassium (218.89 kg ha-1), organic carbon (2.63%) and CEC (14.66 meq 100-1g) were recorded from T3 (75% N through VC one day before transplanting + 25% N through VC 20 DAT). Economics of treatments was calculated and T3 (75% N through VC one day before transplanting + 25% N through VC 20 DAT) recorded highest net return (Rs 5,03,900).The above findings suggest that the application of vermicompost can be effectively used for obtaining higher yield, improve soil fertility and higher net returns for organic cabbage cultivation.

Enhancement of biomass productivity and biochemical composition of alkaliphilic microalgae by mixotrophic cultivation using cheese whey for biofuel production

The growth of microalgae under alkaline conditions ensures an ample supply of CO2 from the atmosphere, with a low risk of crashing due to contamination and predators. The present study investigated the mixotrophic cultivation of two alkaliphilic microalgae (Tetradesmus obliquus and Cyanothece sp.) using cheese whey as an organic carbon source. The variation in cheese whey concentration (0.5–4.5% (v/v)), culture pH (7–11), and NaNO3 concentrations (0–2 gL−1) was evaluated using central composite design in response to biomass productivity and the contents of lipids, total proteins, and soluble carbohydrates. Both investigated microalgae effectively utilized cheese whey as an organic carbon source. The optimum conditions for simultaneously maximizing biomass and lipid productivity in T. obliquus were 3.5% (v/v) whey, pH 10.0, and 0.5 g L−1 NaNO3. Under these conditions, the biomass, lipid, soluble carbohydrate, and protein productivities were 48.69, 20.64, 7.02, and 10.97 mg L−1 day−1, respectively. Meanwhile, Cyanothece produced 52.78, 11.42, 4.31, and 7.89 mg L−1 day−1 of biomass, lipid, carbohydrate, and protein, respectively, at 4.5% (v/v) whey, pH 9.0, and 1.0 g L−1 NaNO3. The lipids produced under these conditions were rich in saturated fatty acids (FAs) and monounsaturated FAs, with no polyunsaturated FAs in both microalgae. Moreover, several biodiesel characteristics were estimated, and results fell within the ranges specified by international standards. These findings indicate that the mixotrophic cultivation of alkaliphilic microalgae could open new avenues for promoting microalgae productivity through low-cost biofuel production.

Depth‐Partitioning of Particulate Organic Carbon Composition in the Rising and Falling Stages of the Amazon River

AbstractThe Amazon River mobilizes organic carbon across one of the world's largest terrestrial carbon reservoirs. Quantifying the sources of particulate organic carbon (POC) to this flux is typically challenging in large systems such as the Amazon River due to hydrodynamic sorting of sediments. Here, we analyze the composition of POC collected from multiple total suspended sediment (TSS) profiles in the mainstem at Óbidos, and surface samples from the Madeira, Solimões and Tapajós Rivers. As hypothesized, TSS and POC concentrations in the mainstem increased with depth and fit well to Rouse models for sediment sorting by grain size. Coupling these profiles with Acoustic Doppler Current Profiler discharge data, we estimate a large decrease in POC flux (from 540 to 370 kg per second) between the rising and falling stages of the Amazon River mainstem. The C/N ratio and stable and radiocarbon signatures of bulk POC are less variable within the cross‐section at Óbidos and suggest that riverine POC in the Amazon River is predominantly soil‐derived. However, smaller shifts in these compositional metrics with depth, including leaf wax n‐alkanes and fatty acids, are consistent with the perspective that deeper and larger particles carry fresher, less degraded organic matter sources (i.e., vegetation debris) through the mainstem. Overall, our cross‐sectional surveys at Óbidos highlight the importance of depth‐specific sampling for estimating riverine export fluxes. At the same time, they imply that this approach to sampling is perhaps less essential with respect to characterizing the composition of POC sources exported by the river.

Variability of Dissolved Organic Matter Sources in the Upper Eurasian Arctic Ocean

AbstractChromophoric dissolved organic matter (CDOM) is a ubiquitous component in marine environments, and substantial changes in its sources and distribution, related to the carbon cycle in the Arctic Ocean, are expected due to Arctic warming. In this study, we present unique CDOM data in the Eurasian Arctic Ocean derived from the year‐round MOSAiC expedition. We used CDOM absorbance spectra and fluorescence excitation‐emission matrices in combination with parallel factor analysis to characterize differences in DOM sources and composition. Our results suggested that terrestrial DOM was less sensitive to seasonal changes but controlled by regionality in hydrography. Elevated dissolved organic carbon (DOC) levels in polar surface water were primarily derived from terrigenous sources as identified by CDOM absorption and fluorescence characteristics. In the Amundsen Basin and western Fram Strait surface waters, to which terrestrial DOM is primarily transported by the Transpolar Drift, we found, on average, a 188% larger meteoric water fraction and a 40% higher DOC concentration compared to the Atlantic water that dominated western Nansen Basin and Yermak Plateau. In the Amundsen Basin, the DOC concentration in summer of surface water was only 13% higher compared to winter season. Additionally, autochthonous DOM and chlorophyll‐a concentrations were relatively low in surface water and exhibited significant differences compared to those observed in summer, while there were significant differences between autochthonous DOM and chlorophyll‐a. We also observed that sea ice melt contributed to autochthonous DOM in summer, while storms in winter affected the vertical distribution of terrestrial and autochthonous DOM in the subsurface.

Quantifying the Potential for Nitrate-Dependent Iron Oxidation on Early Mars: Implications for the Interpretation of Gale Crater Organics.

Geological evidence and atmospheric and climate models suggest habitable conditions occurred on early Mars, including in a lake in Gale crater. Instruments aboard the Curiosity rover measured organic compounds of unknown provenance in sedimentary mudstones at Gale crater. Additionally, Curiosity measured nitrates in Gale crater sediments, which suggests that nitrate-dependent Fe2+ oxidation (NDFO) may have been a viable metabolism for putative martian life. Here, we perform the first quantitative assessment of an NDFO community that could have existed in an ancient Gale crater lake and quantify the long-term preservation of biological necromass in lakebed mudstones. We find that an NDFO community would have the capacity to produce cell concentrations of up to 106 cells mL-1, which is comparable to microbes in Earth's oceans. However, only a concentration of <104 cells mL-1, due to organisms that inefficiently consume less than 10% of precipitating nitrate, would be consistent with the abundance of organics found at Gale. We also find that meteoritic sources of organics would likely be insufficient as a sole source for the Gale crater organics, which would require a separate source, such as abiotic hydrothermal or atmospheric production or possibly biological production from a slowly turning over chemotrophic community.