Recovery Of Fertilizer Research Articles

Influence of fertilization and tillage systems on the humus condition of dark-grey podzolic soil

Topicality. Modern agricultural systems have an ambiguous effect on the humus condition of soils. The urgent task is to restore and preserve the fertility of the dark grey podzolic soil and increase the organic matter content in the agricultural system. Purpose. To determine changes in the humus condition of dark grey podzolic soil under sunflower under different tillage and fertilisation systems using crop rotation by-products. Materials and methods. In the long-term stationary experiment, the following tillage systems were used: ploughing at a depth of 25–27 cm, disking at 15–17 cm and disking at 10–12 cm. Ploughing under sunflower was carried out with plough PLN-3-35, disking – disc harrow AG-2.4-20. The fertilisation systems were as follows: 1) no by-products; 2) by-products; 3) N10 (ammonium nitrate) per 1 tonne of by-products. The humus content in the soil was determined according to the I.V. Tyurin’s method, the group composition of humus – according to method of M. M. Kononova and N. P. Bielchikova. Results. It was established that the highest humus content in the 0–20 cm layer of the soil under sunflower was 2.09 % for the variant with disking at a depth of 15–17 cm using by-products. On dark grey podzolic soil, humus accumulation is enhanced by disking at 15–17 cm and fertilisation with by-products and N10, which is accompanied by characteristic changes such as an increase in the total content of humic acids and non-hydrolysed residue in the humus group composition. The highest content of humic acids was 0.29–0.34 % in the plots with moldboardless tillage under different fertilisation systems. The lowest content of this important humus fraction was 0.23–0.25 % in the variant with different depth ploughing. In the variants with disking to a depth of 15–17 cm and 10–12 cm when using by-products with N10, the highest values of the ratio between carbon in humic acids and carbon in fulvic acids were 1.26 and 1.27, respectively. Conclusions. Application of moldboardless tillage, disking at a depth of 15–17 cm and fertilisation system with by-products + N10 contribute to the recovery of dark grey podzolic soil fertility and improvement of its humus condition. In Western Polissia of Ukraine, it is recommended to carry out disking at a depth of 15–17 cm with the use N10 per 1 ton of by-products in the fertilisation system for sunflower cultivation. Key words: humus, dark grey podzolic soil, fertilization system, humic acids, fulvic acids

Fate of fertiliser nitrogen in a ryegrass–kikuyu dairy pasture system

Context Dairy pasture production is reliant on fertiliser to supply nitrogen (N); however, fertiliser N-use efficiency (FNUE) is low and N can be lost to the environment. Aims The aim of this study was to track the fate of N fertiliser applied in a pasture system of ryegrass (Lolium multiflorum, temperate grass) oversown into kikuyu (Pennisetum clandestinum, tropical grass). Methods We used 15N-labelled urea to track the residual plant uptake of a one-off application of 15N over three pasture cuts subsequent to the first cut in the kikuyu growing season from February 2018 to April 2018 (Experiment 1), followed by total soil and plant recoveries of 15N over a 12-month period (Experiment 2). Total N treatment rates were 0, 120, 240 and 480 kg N ha−1 year−1, consisting of application events of 40 kg N ha−1. In Experiment 1, 15N was applied only at the first fertilisation, whereas in Experiment 2, 15N-labelled urea was applied at each fertilisation event. Key results In Experiment 1, uptake of residual 15N fertiliser in the pasture biomass was <6%. In Experiment 2, FNUE was 29–32% and unaccounted 15N fertiliser was 22–142 kg N ha−1, across the 120, 240 and 480 kg N ha−1 year−1 treatments. Conclusions Recovery of 15N residual fertiliser did not increase with N rate and was attributed to the mass increase in soil 15N recovery. FNUE in the pasture did not decrease with N rate. Unaccounted 15N increased with N rate. Implications Existing and alternative N and pasture management strategies such as clover and multi-species pasture need to be implemented and explored to reduce the amount of unaccounted N in dairy pasture production.

Nitrate leaching losses and the fate of 15N fertilizer in perennial intermediate wheatgrass and annual wheat - A field study.

Perennial grains, such as the intermediate wheatgrass (Thinopyrum intermedium) (IWG), may reduce negative environmental effects compared to annual grain crops. Their permanent, and generally larger, root systems are likely to retain nitrogen (N) better, decreasing harmful losses of N and improving fertilizer N use efficiency, but there have been no comprehensive N fertilizer recovery studies in IWG to date. We measured fertilizer N recovery with stable isotope tracers in crop biomass and soil, soil N mineralization and nitrification, and nitrate leaching in IWG and annual wheat in a replicated block field experiment. Nitrate leaching was drastically reduced in IWG (0.1 and 3.1 kg N ha-1 yr-1) in its third and fourth year since establishment, compared with 5.6 kg N ha-1 yr-1 in annual wheat and 41.0 kg N ha-1 yr-1 in fallow respectively. There were no differences in net N mineralization or nitrification between IWG and annual wheat, though there was generally more inorganic N in the soil profile of annual wheat. More 15N fertilizer was recovered in the straw and all depths of the roots and soils in IWG than annual wheat. However, annual wheat recovered much more 15N fertilizer in the seeds compared to IWG, which had lower grain yields. 15N-labeled fertilizer contributed little (<3 %) to nitrate-N in leachate, highlighting the role of soil microbes in regulating loss of current year fertilizer N. The large reduction in nitrate leaching demonstrates that perennial grains can reduce harmful nitrogen losses and offer a more sustainable alternative to annual grains.

The central cell: another opportunity for fertilization recovery in plants

The central cell: another opportunity for fertilization recovery in plants

Fertility recovery despite the COVID-19 pandemic in Finland?

Finland’s increase in births, recorded in the months following the first two waves of the COVID-19 pandemic, was among the strongest. We assess whether this fertility increase occurred because of or despite the pandemic, or both, by investigating the country’s fertility trends by women’s region of residence, age group, and parity. Finland overall was modestly hit by the early pandemic, but Helsinki-Uusimaa faced more severe restrictions. We used aggregate register data until September 2021 to assess monthly fertility. In 2020 and 2021, the relative increases in fertility were strongest among women aged 30 and over. In 2021, but not in 2020, fertility increased most in Helsinki-Uusimaa, and across parities. Model-based estimates suggested a modest fertility boost of the early pandemic. To conclude, Finland’s notable fertility increase in 2021 broadly followed pre-existing trends where the country recovered from its all-time low fertility levels, and the early pandemic may have reinforced this trend.

The effect of catch crops in spring barley on nitrate leaching and their fertilizer replacement value

Catch crops have been proven effective in reducing nitrogen leaching in cropping systems due to their uptake of post-harvest soil mineral N prior to the main percolation season in winter. Information on the residual effect of catch crops, and their nitrogen fertilizer replacement value is scarce. To determine nitrogen fertilizer replacement values for different catch crops a field experiment was conducted over a four-year period on a sandy soil in Denmark, involving different catch crops and catch crop mixtures with non-legume and legume species. The residual effect of the catch crops was measured in spring barley grown in the residual year. For comparison, winter rye was also included. Over the four-year period the spring barley/fodder radish showed significantly lower leaching compared with the other catch crops, and the winter rye had the highest leaching. Regarding the residual effect, fodder radish and ryegrass, were most valuable, with nitrogen fertilizer replacement values ranging from 13 to 41 kg ha-1, based on fertilizer recovery efficiency of 50%. The process based APSIM (Agricultural Production Systems sIMulator) model was used to simulate the spring barley/catch crop rotations and the winter rye, and showed good model performance regarding N leaching and, crop yield and N uptake. The model was then run over a period of 20 years, to determine variations in N leaching and residual effects due to environmental conditions. The simulations showed that catch crops reduced N leaching by 38–64% when grown every year, and by 21–39% when grown only every second year. Nitrogen fertilizer replacement values ranged on average from 28 to 44 kg N ha-1, but showed high inter-annual variability. The nitrogen fertilizer replacement values showed only a weak relationship with the N uptake of the catch crop prior to termination, likely due to long term effects of N mineralisation from catch crop residues and pre-emptive competition for N by the catch crop.

Matured Manure and Compost from the Organic Fraction of Solid Waste Digestate Application in Intensive Apple Orchards

In intensive fruit growing systems, the recovery and maintenance of soil fertility play a crucial role in both environmental protection and sustainable support to plant productivity. The circular economy approach adopted at the EU level strongly promotes the use of organic products instead of mineral fertilizers. This work focuses on two different soil improvers, compost from the organic fraction of municipal solid waste digestate (CO) and "matured" manure, produced after a fast and controlled aerobic treatment in an aerated pile (MM), which were applied in three apple orchards with different soil tillage. The soil improvers have been characterized for amendment and fertilizing properties. After the amendment, the soils were sampled twice a year (Spring and Autumn) for three years. Each sample has been characterized for texture, pH, cation exchange capacity, nutrients, soil organic matter, and micronutrients. The amendments obtained differed on C, N, P, and K contents, but had similar biological stability. The main effects on soils were the increasing of N and soil organic matter after compost application, while the use of matured manure mainly act on available P and exchangeable K. The treatments showed significant effects among fields with a linear increasing trend only for compost. Matured manure showed more effects in earlier times. The data collected aim to improve the knowledge about sustainable management of soil organic matter and organic nutrients in intensive fruit-growing agriculture by using local products.

Is autologous platelet activation the key step in ovarian therapy for fertility recovery and menopause reversal?

Platelets are a uniquely mammalian physiologic feature. As the only non-marine vertebrates to experience menopause, humans have a substantial post-reproductive lifespan and are believed to have a limited, non-renewable oocyte supply. Ovarian reserve typically declines after about age 35yrs, marking losses which cannot be recovered by available fertility medications. When in vitro fertilization fails due to low or absent ovarian response, gonadotropin adjustments are often ineffectual and if additional oocytes are occasionally harvested, egg quality is usually poor. This problem was confronted by Greek researchers who developed a new surgical method to insert autologous platelet-rich plasma (PRP) into ovaries; the first ovarian PRP success to improve reproductive outcomes was published from Athens in 2016. This innovation influenced later research with condensed platelet-derived growth factors, leading to correction of oocyte ploidy error, normal blastocyst development, and additional term livebirths. Yet women's health was among the last clinical domains to explore PRP, and its role in 'ovarian rejuvenation' remains unsettled. One critical aspect in this procedure is platelet activation, a commonly overlooked step in the cytokine release cascade considered essential for successful transition of undifferentiated ovarian stem cells to an oocyte lineage. Poor activation of platelets thus becomes an unforced error, potentially diminishing or even negating post-treatment ovarian follicular response. To answer this query, relevant theory, current disagreements, and new data on platelet activation are presented, along with clinical challenges for regenerative fertility practice.

Nitrogen Availability Drives Mycorrhizal Effects on Wheat Growth, Nitrogen Uptake and Recovery under Salt Stress

The arbuscular mycorrhizal (AM) symbiosis is generally considered effective in improving salt tolerance in plants; however, the advantages it offers can vary greatly depending on the context in which it occurs; furthermore, the mechanisms underlying these responses are still unclear. A study was conducted to investigate the role of nitrogen (N) availability on the effectiveness of AM symbiosis in durum wheat (Triticum durum Desf.) plants grown under salt stress. Plants were grown in pots in the absence or in presence of salt stress (soil electrical conductivity of 1.50 and 13.00 dS m−1, respectively), with or without AM fungi inoculation (Rhizophagus irregularis and Funneliformis mosseae), varying the N dose supplied (0 or 80 mg N per pot). Results indicate that AM symbiosis can alleviate the detrimental effects of salt stress on the growth of durum wheat only when plants are grown under sufficient N availability in soil; in such conditions mycorrhizal symbiosis determined an improvement of leaf traits (leaf area, SLA, stability of plasma membranes and SPAD), N uptake, N fertilizer recovery and water use efficiency. On the contrary, when wheat plants were grown in conditions of N deficiency, the mycorrhizal symbiosis had no effect (under salt stress) or even depressive effect (under unstressed condition) on plant growth and N uptake, highlighting how, in some cases, competition for nutrients between plants and AM can arise. This study suggests that N availability in the soil can drive the effects of AM symbiosis in assisting the plant with containing saline stress.

The egg cell is preferentially fertilized in Arabidopsis double fertilization.

In flowering plants (angiosperms), fertilization of the egg cell by one sperm cell produces an embryo, whereas fusion of a second sperm cell with the central cell generates the endosperm. In most angiosperms like Arabidopsis, a pollen grain contains two isomorphic sperm cells required for this double fertilization process. A long-standing unsolved question is whether the two fertilization events have any preference. A tool to address this question is the usage of the cyclin-dependent kinase a1 (cdka;1) mutant pollen, which produces a single sperm-like cell (SLC). Here, we first adopt a complementation-based fluorescence-labeling method to successfully separate and collect cdka;1 mutant pollen containing a single SLC. Single-cell RNA-sequencing analysis revealed that cdka;1 SLCs show a gene expression profile highly similar to that of sperm cells and not to the generative cell, precursor of the two sperm cells. Pollination assays using a limited number of cdka;1 mutant pollen revealed that in 98.2% of the ovules, single fertilization of the egg cell occurred. Pollination of pistils with excessive cdka;1 mutant pollen allowed the delivery of a second SLC via fertilization recovery, which fertilized the central cell, resulting in 20.7% double-fertilized ovules. This indicates that cdka;1 SLCs are able to fertilize both the egg and the central cell. Taken together, our findings have answered a long-standing question and support that preferential fertilization of the egg cell is evident in Arabidopsis.

Application of Pulsed Potential Waveform in Electrochemical Phosphate Recovery As Struvite from Wastewater

Phosphate production is apprehended to peak as early as 2030, and post-peak, phosphate production, and thus food supply, will be limited by dwindling resources, strained economics, and reduced rock quality, with remaining resources expected to last 50-300 years. The limited supply of phosphate demands P conservation by changing the food production system, from fertilization to wastewater treatment. Stuvite (MgNH4PO4.6H2O) has been recognized as a high-value, slow-release, effective fertilizer that can be obtained from both solid (e.g., food, animal, and human waste) and liquid wastes (e.g., wastewater from industrial, municipal, and agricultural operations). The goal of our research is to recover struvite from wastewater using an alkaline electrochemical reactor with a magnesium alloy anode and a cathode constructed of standard catalysts for reducing water to hydrogen gas and hydroxide. Over time with successive reactor batches, the magnesium electrode used to generate magnesium cations in solution and precipitate struvite becomes severely fouled, which in turn increases energy demand and decrease struvite fertilizer recovery. A dynamic, pulsed voltage waveform, as opposed to a constant voltage, causes a stress-strain-like effect at the magnesium electrode surface, thereby preventing or reducing the amount of struvite precipitate that would attach to the electrode. In an aqueous solution of ammonium dihydrogen phosphate (NH4H2PO4, 10 mM) at neutral pH, a significant 50% increase in magnesium release is observed compared to constant voltage applications, resulting in a 30% increase in phosphate recovery. Studies of the recovered precipitate using X-ray diffraction and scanning electron microscopy (SEM) indicate the presence of struvite.

Carob extract induces spermatogenesis in an infertile mouse model via upregulation of Prm1, Plzf, Bcl-6b, Dazl, Ngn3, Stra8, and Smc1b

Ethnopharmacological relevanceEthnopharmacological studies for drug discovery from natural compounds play an important role for developing current therapeutical platforms. Plants are a group of natural sources which have been served as the basis in the treatment of many diseases for centuries. In this regard, Ceratonia siliqua (carob) is one of the herbal medicine which is traditionally used for male infertility treatments. But so far the main mechanisms for effects of carob are unknown. Here, we intend to investigate the ability of carob extract to induce spermatogenesis in an azoospermia mouse model and determine the mechanisms that underlie its function. Aim of the studyThis is a pre-clinical animal model study to evaluate the effect of carob extract in spermatogenesis recovery. MethodsWe established an infertile mouse model with the intent to examine the ability of carob extract as a potential herbal medicine for restoration of male fertility. Sperm parameters, as well as gene expression dynamics and levels of spermatogenesis hormones, were evaluated 35 days after carob administration. ResultsSignificant enhanced sperm parameters (P < 0.05) showed that the carob extract could induce spermatogenesis in the infertile mouse model. Our data suggested an anti-apototic and inducer role in the expressions of cell cycle regulating genes. Carob extract improved the spermatogenesis niche by considerable affecting Sertoli and Leydig cells (P < 0.05). The carob-treated mice were fertile and contributed to healthy offspring that matured. Our data confirmed that this extract triggered the hormonal system, the spermatogenesis-related gene expression network, and signaling pathways to induce and promote sperm production with notable level (P < 0.05). We found that the aqueous extract consisted of a polar and mainly well water-soluble substance. Carob extract might upregulate spermatogenesis hormones via its amino acid components, which were detected in the extract by liquid chromatography-mass spectrometry (LC-MS). ConclusionOur results strongly suggest that carob extract might be a promising future treatment option for male infertility. This finding could pave the way for clinical trials in infertile men. This is the first study that has provided reliable, strong pre-clinical evidence for carob extract as an effective candidate for fertility recovery in cancer-related azoospermia.

Circular economy in biorefineries: Scale-up of anaerobic/aerobic membrane bioreactors for vinasse recycling

The increased ethanol production driven by the growing demand for biofuels have the generation of vinasse as a negative aspect. Aiming for vinasse recycling, this study compared the performance of aerobic (AeMBR) and anaerobic (AnMBR) membrane bioreactors as alternatives for water, energy, and fertilizer recovery. In terms of organic matter, the AnMBR demonstrated a better removal efficiency (RAnMBR: 97%, RAeMBR: 92%) with significant differences. Higher values of chemical oxygen demand (COD) in the AeMBR permeate were correlated with the higher production of soluble microbial products and external polymeric substances. The opposite was observed in terms of total nitrogen removal since AeMBR showed better efficiency (RAeMBR: 80%, RAnMBR: 56%). Due to the higher fouling rate, the AeMBR required a higher increase in transmembrane pressure to guarantee a constant permeate flux and more frequent interruptions for membrane cleaning and maintenance. It would be able to recover 527 m³/h of permeate to be used in cane washing procedures or as feedstock for fertilizer obtainment, the latter with the expectations of better reuse of vinasse nutrients and lower environmental impacts compared with fertigation practices. Their demand (water and fertilizer), aligned with economic aspects, should be considered when deciding on the best reuse alternative. The AnMBR presented a higher operational cost (0.515 US$/m³) compared with the AeMBR (0.441 US$/m³). Nevertheless, the system allowed to recover 6.1 Nm³-CH4/m³-vinasse, which represents an energy production potential of 26.1 kW/m³-vinasse. Overall, the systems would allow for the higher valorization of vinasse, with better use of wastes and contributing to less dependence on raw materials.

Enhanced susceptibility to oiling may limit denitrification recovery in marshes subjected to woody encroachment

Coastal salt marshes provide valuable ecosystem services but are subjected to multiple concomitant stressors that may impact their ability to provide those services. Global climate change has led to the poleward expansion of mangroves into salt marshes on each continent where mangroves and marshes co-occur. In the northern Gulf of Mexico, warming winter temperatures have resulted in the expansion of Avicennia germinans (black mangrove) into forb-dominated salt marshes, resulting in a shift in ecosystem structure that can impact the ecosystem services marshes provide, including biogeochemical processes such as nitrogen removal. There have been limited studies addressing how mangrove expansion impacts nitrogen removal rates in salt marshes, but it is possible that mangroves enhance microbial nitrogen removal capacity through more efficient oxygen translocation to sediments. However, mangroves are more sensitive to oiling (such as occurred during the 2010 Deepwater Horizon spill) than marsh plants, such as Spartina alterniflora, which have a higher turnover. Thus, even if they enhance nitrogen removal, if they cannot withstand disturbances such as oiling, there still may be a loss of function associated with woody encroachment. We conducted a field study to assess the impact of woody encroachment in mediating biogeochemical recovery 7 to 8 years after the Deepwater Horizon oil spill. We collected sediments from S. alterniflora- and A. germinans-dominated plots in the Chandeleur Islands (LA, United States), a chain of barrier islands in the northern Gulf of Mexico subjected to a range of oiling following the spill. We compared nitrate reduction rates (denitrification and dissimilatory nitrate reduction to ammonium), microbial community composition, and denitrifier marker gene abundance at sites subjected to light and moderate oiling using a combination of isotope pairing on sediment slurries, 16S sequencing, and qPCR. We predicted that overall, denitrification rates and microbial functional capacity would be enhanced in mangrove-dominated sediments. We also predicted that these enhancements would be diminished at the more intensely oiled site due to the higher susceptibility of A. germinans to oiling. Denitrification potential rates were higher in mangrove sediments at the lightly oiled site, whereas dissimilatory nitrate reduction to ammonium potential rates were higher in marsh sediments. Indicator analysis of 16S rRNA data selected putative sulfur cycling taxa as indicators of marsh sediments, suggesting that changes in oxygen availability associated with encroachment may be driving the differences in process rates. There was no difference in process rates between plant types at the moderately oiled site, where heavily weathered oil residue was still present. Sediment nutrient stocks were lower in moderately oiled mangrove plots than in lightly oiled mangrove plots, suggesting that sediment fertility recovery following the spill may have been slower in the mangroves, contributing to a change in ecosystem function. This study shows that woody encroachment has the potential to impact both the biogeochemical services that marshes provide and their response to and recovery from disturbances.

Cover Crops Increase N and P Cycling and Rice Productivity in Temperate Cropping Systems

Cover crops can determine positive benefits on soil fertility and rice productivity, although scant attention has been devoted to evaluating the effects of hairy vetch (Vicia villosa Roth) and the incorporation of rice straw with different N fertilization levels on soil N and P availability and crop yields in temperate cropping systems characterized by poorly developed soils. In this study, the effects of cover crops grown before rice in a temperate mono-cropping system (NW Italy) on: (i) crop yields and yield components; (ii) apparent N fertilizer recovery and optimal level of N fertilization with hairy vetch; and (iii) temporal variation of soil available N and P forms during the hairy vetch growth and rice cropping season, have been investigated. The cultivation and incorporation of hairy vetch in the rice cropping system increased grain productivity by 12%, while reducing N mineral fertilization requirements by 33%. Combined with the incorporation of crop residues, hairy vetch provided a N and P input of 178 and 18 kg ha−1, respectively, representing a readily available source for plant uptake over the whole rice cropping season, particularly under anaerobic conditions. This results in a better temporal synchronization of soil N and P availability with crop nutrient demand, leading to a better rice grain productivity and quality performance.

Impact of Organic and Chemical Nitrogen Fertilizers on the Crop Yield and Fertilizer Use Efficiency of Soybean–Maize Intercropping Systems

The effect of the mixture (1:1) of chemical and organic nitrogen (N) fertilizer on crop yield quality and N fertilizer use efficiency remains elusive. A nitrogen field experiment was conducted in the growing seasons of 2020 and 2021 to investigate the effects of the mixture of chemical and organic N fertilizer on the crop yield, crop quality and nitrogen fertilizer use efficiency in a maize–soybean intercropping system in China. Four treatments applied at 150 kg N ha−1 were used: no nitrogen fertilizer (CK), chemical N fertilizer (ChemF), mixture (1:1) of chemical and organic N fertilizer (ChemF + OrgF) and organic N fertilizer (OrgF). The results showed that the yield and aboveground N accumulation of both soybean and maize increased with the application of fertilizer. The ChemF + OrgF treatment had lower maize and soybean seed yields than for ChemF treatment, but higher than the other two treatments in both years, and the maize yield of the (ChemF + OrgF) treatment was significantly higher (14.9%) in 2021 than 2020. Yields were significantly positively correlated with aboveground N accumulation and fertilizer use efficiency, measured using the nitrogen partial productivity (NPP), nitrogen agronomic efficiency (NAE) and nitrogen fertilizer recovery rate (NFRR). The protein content tended to increase and the oil content tended to decrease under (ChemF + OrgF) applications in soybeans. The (ChemF + OrgF) treatment had the lowest starch content in maize. There was no significant difference in the nitrogen harvest index among treatments, while the NPP, NAE and NFRR were the highest for the application of chemical N fertilizer and significantly decreased with the addition of organic N fertilizer. We conclude that the mixture (1:1) of chemical and organic N fertilizer increased the seed yield and quality of maize, but only the seed yield of soybean.

Use of vermicompost for recovery of soil fertility and increase of field crop capacity increase under conditions of the dry-steppe zone

Use of vermicompost for recovery of soil fertility and increase of field crop capacity increase under conditions of the dry-steppe zone

Recovery of nitrogen fertilizer can be doubled by urea-briquette deep placement in rice paddies

Nitrogen (N) recoveries in rice paddies have barely exceeded 60%, despite the implementation of several management strategies, amounting to significant N being lost to the environment. We conducted field experiments for three consecutive rice growing seasons at two locations in Myanmar to investigate the performance of urea-briquette deep placement (UDP) against variable rates of surface broadcast urea for improving N recovery and yields in rice paddies. The experiment consisted of a control (N0), 77.6 kg N ha−1 as UDP, and surface broadcast urea at 77.6 kg N ha−1 (N78), 100 kg N ha−1 (N100) and 160 kg N ha−1 (N160). Surface broadcast urea was applied in two equal splits at 10 days after transplanting (10 DAT) and at panicle initiation (PI) stage. Urea briquettes (2.7 g) were deep placed (75 mm) in the middle of four rice hills between alternate rows as a single dose at 10 DAT. Microplots receiving 15N labeled urea were installed in each treatment plot (except N100) to trace the fate of the applied N. Nitrogen input almost always produced higher grain yields (p < 0.05) compared to the control. Rice grain yield in the UDP treatment was similar or higher than in the N78, N100 and N160 treatments. Crop dry biomass yield in the UDP treatment was mostly higher (p < 0.05) than in the N78 and always similar to the N160 treatment. Higher crop (47–61%) and soil (24–40%) recovery of 15N was observed in the UDP treatment than in the N78 and N160 treatments, leading to total recoveries of 77–95%. The N78 treatment had crop recoveries of 30–37% and total recoveries of 41–60% and the N160 treatment had crop recoveries of 29–39% and total recoveries of 40–54%. The rice plants in the UDP treatment relied less on native soil N, indicating that the UDP practice can minimize soil N depletion. Our results show that UDP has substantial advantages over surface broadcasting in terms of N fertilizer recovery and may provide environmental benefits.

Design and preliminary techno-economic assessment of a pilot scale pharmaceutical wastewater treatment system for ammonia removal and recovery of fertilizer

Recovery of nutrients from wastewater has a paramount importance for a sustainable and safe environment. In this study removal of ammonia and recovery of resources in the form of struvite from a complex pharmaceutical acidic wastewater having high concentration of ammoniacal nitrogen (NH4–N > 40 g/L) and other co-existing contaminants (magnesium, phosphorous, phenol etc.) was explored. Response Surface Methodology (RSM) was employed for design of experiments and process optimization. RSM results revealed that removal of ammoniacal nitrogen, i.e., struvite precipitation was found to be maximum in alkaline pH (10.5–11.0) at a N:Mg molar ratio (1:0.030 to 1:0.035) and N:P molar ratio (1:0.025 to 1:0.030). X-Ray diffraction, thermo-gravimetric analysis and Fourier transform-infrared spectroscopy confirmed the presence of struvite crystals in the obtained precipitate. Techno-economic assessment (TEA) based on mass energy balance principle and market equipment specifications revealed that a pilot-scale plant set up would have a break-even period of 1.06 years with a return on investment as 94.28%. This clearly elucidated the economic viability of the developed process for industrial applications for management of high ammonia laden pharmaceutical wastewater. While further specific technological improvements are needed for reduction of cost, this study will guide researchers and industries for careful selection of target markets to reduce the cost for successful implementation.

Melatonin enhances autologous adipose-derived stem cells to improve mouse ovarian function in relation to the SIRT6/NF-κB pathway

BackgroundPremature ovarian insufficiency (POI) is the main cause of female infertility. Adipose-derived stem cells (ADSCs) are ideal candidates for the treatment of POI. However, some deficient biological characteristics of ADSCs limit their utility. This study investigated whether melatonin (MLT)-pretreated autologous ADSCs were superior to ADSCs alone in the treatment of the POI mouse model.MethodsAutologous ADSCs were isolated and cultured in MLT-containing medium. Surface markers of ADSCs were detected by flow cytometry. To determine the effect of MLT on ADSCs, CCK-8 assay was used to detect ADSCs proliferation and enzyme-linked immunosorbent assay (ELISA) was used to detect the secretion of cytokines. The POI model was established by intraperitoneal injection of cyclophosphamide and busulfan. Then, MLT-pretreated autologous ADSCs were transplanted into mice by intraovarian injection. After 7 days of treatment, ovarian morphology, follicle counts, and sex hormones levels were evaluated by hematoxylin and eosin (H&E) staining and ELISA, and the recovery of fertility was also observed. The expressions of SIRT6 and NF-κB were detected by immunohistochemical (IHC) staining and quantitative real-time polymerase chain reaction (qRT-PCR).ResultsFlow cytometry showed that autologous ADSCs expressed CD90 (99.7%) and CD29 (97.5%). MLT can not only promote the proliferation of ADSCs but also boost their secretory function, especially when ADSCs were pretreated with 5 µM MLT for 3 days, improving the interference effect. After transplantation of autologous ADSCs pretreated with 5 µM MLT, the serum hormone levels and reproductive function were significantly recovered, and the mean counts of primordial follicle increased. At the same time, the expression of SIRT6 was remarkably increased and the expression of NF-κB was significantly decreased in this group.ConclusionsMLT enhances several effects of ADSCs in restoring hormone levels, mean primordial follicle counts, and reproductive capacity in POI mice. Meanwhile, our results suggest that the SIRT6/NF-κB signal pathway may be the potential therapeutic mechanism for ADSCs to treat POI.