The chemical interaction of biochar with iron and phosphate might explain the effects of biochar in alkaline and calcareous soils

<p>Due to the low consistency of the results obtained in field, the use of biochar as soil amendment is controversial. Thus, in general in acidic soils results are positive while in alkaline soils they are non-significant or even negative. The results regarding biochar action in acidic soils have been related to a lime-like effect due to its alkaline pH and the high doses normally used. However, the causes of biochar effects in alkaline soils remain unknown. We have used a well characterized biochar as a component of two complex N and PK granulated fertilizers at two different doses (1 and 5%). These fertilizers have been applied to wheat cultivated in pots containing an alkaline and calcareous soil and grown for 60 days. No effect was shown for the N-biochar fertilizer application. However, the PK-biochar fertilizer application caused a decrease in crop yield. Complementary, the absorption isotherms of Iron (Fe), Molybdenum (Mo), Manganese (Mn) and Phosphate (Pi) in biochar were also studied. The results showed that Fe was rapidly adsorbed in biochar, while Pi was only absorbed on the Fe-Biochar complex. Desorption experiments showed that P and Fe were no desorbed from the P-Fe-biochar complex by water or the Olsen reactant, while a partial desorption was observed when HCl 0.1 M was used. This blockage of Fe and P through Fe bridges in biochar could partially explain the negative effects in alkaline soils.</p>

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Biochar-Ca and Biochar-Al/-Fe-Mediated Phosphate Exchange Capacity are Main Drivers of the Different Biochar Effects on Plants in Acidic and Alkaline Soils

Agronomy ◽

10.3390/agronomy10070968 ◽

2020 ◽

Vol 10 (7) ◽

pp. 968 ◽

Cited By ~ 1

Author(s):

Roberto Baigorri ◽

Sara San Francisco ◽

Óscar Urrutia ◽

José María García-Mina

Keyword(s):

Fertilizer Application ◽

Exchange Capacity ◽

Chemical Mechanism ◽

Alkaline Soil ◽

Alkaline Soils ◽

Negative Effects ◽

Acidic Soils ◽

High Doses ◽

Phosphate Exchange ◽

Partial Desorption

Because of the low consistency of the results obtained in the field, the use of biochar as a soil amendment is controversial. Thus, in general, in acidic soils, results are positive, while in alkaline soils, they are non-significant or even negative. The results regarding biochar action in acidic soils have been related to a lime-like effect due to its alkaline pH and the high doses normally used. However, the causes of biochar effects in alkaline soils remain unknown. Our objective was to explore the chemical mechanism of biochar interaction in acidic and alkaline soils. We used well-characterized biochar as a component of two complex N and PK granulated fertilizers at two different doses (1% and 5%). These fertilizers were applied to wheat cultivated in pots containing an alkaline soil and grown for 60 days. No effect was shown for the N-biochar fertilizer application. However, the PK-biochar fertilizer application caused a decrease in crop yield. In addition, the adsorption isotherms of Al, Fe, Mo, Mn, and Phosphate (Pi) in biochar were also studied. The results showed that Fe and Al were rapidly adsorbed in biochar, while Pi was only adsorbed on the Fe-, Al-biochar complex. Desorption experiments showed that P and Fe/Al were not desorbed from the P-Fe/Al-biochar complex by water or the Olsen reagent, while partial desorption was observed when HCl 0.1 M was used. This blockage of Fe/Al and P through Fe/Al bridges in biochar could partially explain the negative effects in alkaline soils. After these studies, soil solution sorption experiments were carried out in both acidic and alkaline soils and were complemented with a greenhouse trial using tomato plants. The results showed that biochar enhanced foliar Ca and N content, as well as growth in acidic soil only, and the possible mechanism of the failure in alkaline soils.

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Effects of Two Different Doses of Hirudin on APTT, Determined with Eight Different Reagents

Thrombosis and Haemostasis ◽

10.1055/s-0038-1653754 ◽

1995 ◽

Vol 73 (02) ◽

pp. 219-222 ◽

Cited By ~ 4

Author(s):

Manuel Monreal ◽

Luis Monreal ◽

Rafael Ruiz de Gopegui ◽

Yvonne Espada ◽

Ana Maria Angles ◽

...

Keyword(s):

Ex Vivo ◽

Anticoagulant Activity ◽

Subcutaneous Administration ◽

In Vitro Study ◽

Ex Vivo Model ◽

Suitable Candidate ◽

Significant Prolongation ◽

High Doses ◽

Different Doses

SummaryThe APTT has been considered the most suitable candidate to monitor the anticoagulant activity of hirudin. However, its use is hampered by problems of standardization, which make the results heavily dependent on the responsiveness of the reagent used. Our aim was to investigate if this different responsiveness of different reagents when added in vitro is to be confirmed in an ex vivo study.Two different doses of r-hirudin (CGP 39393), 0.3 mg/kg and 1 mg/kg, were administered subcutaneously to 20 New Zealand male rabbits, and the differences in prolongation of APTT 2 and 12 h later were compared, using 8 widely used commercial reagents. All groups exhibited a significant prolongation of APTT 2 h after sc administration of hirudin, both at low and high doses. But this prolongation persisted 12 h later only when the PTTa reagent (Boehringer Mannheim) was used. In general, hirudin prolonged the APTT most with the silica- based reagents.In a further study, we compared the same APTT reagents in an in vitro study in which normal pooled plasma was mixed with increasing amount of hirudin. We failed to confirm a higher sensitivity for silica- containing reagents. Thus, we conclude that subcutaneous administration of hirudin prolongs the APTT most with the silica-based reagents, but this effect is exclusive for the ex vivo model.

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Melatonin actions in the heart; more than a hormone

Melatonin Research ◽

10.32794/mr11250002 ◽

2018 ◽

Vol 1 (1) ◽

pp. 21-26 ◽

Cited By ~ 9

Author(s):

Darío Acuña-Castroviejo ◽

Maria T Noguiera-Navarro ◽

Russel J Reiter ◽

Germaine Escames

Keyword(s):

Cell Membranes ◽

Myocardial Cell ◽

Rat Tissues ◽

Dependent Manner ◽

Broad Distribution ◽

Multiple Organs ◽

High Doses ◽

Extrapineal Melatonin ◽

Dose Dependent ◽

Different Doses

Due to the broad distribution of extrapineal melatonin in multiple organs and tissues, we analyzed the presence and subcellular distribution of the indoleamine in the heart of rats. Groups of sham-operated and pinealectomized rats were sacrificed at different times along the day, and the melatonin content in myocardial cell membranes, cytosol, nuclei and mitochondria, were measured. Other groups of control animals were treated with different doses of melatonin to monitor its intracellular distribution. The results show that melatonin levels in the cell membrane, cytosol, nucleus, and mitochondria vary along the day, without showing a circadian rhythm. Pinealectomized animals trend to show higher values than sham-operated rats. Exogenous administration of melatonin yields its accumulation in a dose-dependent manner in all subcellular compartments analyzed, with maximal concentrations found in cell membranes at doses of 200 mg/kg bw melatonin. Interestingly, at dose of 40 mg/kg b.w, maximal concentration of melatonin was reached in the nucleus and mitochondrion. The results confirm previous data in other rat tissues including liver and brain, and support that melatonin is not uniformly distributed in the cell, whereas high doses of melatonin may be required for therapeutic purposes.

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The Effects of N-Acetylcysteine on the Rat Mesocorticolimbic Pathway: Role of mGluR5 Receptors and Interaction with Ethanol

Pharmaceuticals ◽

10.3390/ph14060593 ◽

2021 ◽

Vol 14 (6) ◽

pp. 593

Author(s):

Sandra Fernández-Rodríguez ◽

Claudia Esposito-Zapero ◽

Teodoro Zornoza ◽

Ana Polache ◽

Luis Granero ◽

...

Keyword(s):

Behavioral Activation ◽

Ethanol Administration ◽

Metabotropic Receptors ◽

Negative Allosteric Modulator ◽

High Doses ◽

Cell Expression ◽

Mucolytic Agent ◽

Different Doses

N-acetylcysteine (NAC) is a prodrug that is marketed as a mucolytic agent and used for the treatment of acetaminophen overdose. Over the last few decades, evidence has been gathered that suggests the potential use of NAC as a new pharmacotherapy for alcohol use disorder (AUD), although its mechanism of action is already being debated. In this paper, we set out to assess both the potential involvement of the glutamate metabotropic receptors (mGluR) in the possible dual effect of NAC administered at two different doses and NAC’s effect on ethanol-induced activation. To this aim, 30 or 120 mg/kg of NAC was intraperitoneally administered to rats with the presence or absence of the negative allosteric modulator of mGluR5 (MTEP 0.1 mg/kg). Thereafter, the cFOS IR-cell expression was analyzed. Secondly, we explored the effect of 120 mg/kg of NAC on the neurochemical and behavioral activation induced by intra-VTA ethanol administration (150 nmol). Our results showed that the high NAC dose stimulated cFOS expression in the NAcc, and that this effect was suppressed in the presence of MTEP, thus suggesting the implication of mGluR5. Additionally, high doses could attenuate the ethanol-induced increase in cFOS-expression in the NAcc, probably due to a phenomenon based on the long-term depression of the MSNs. Additional experiments are required to corroborate our hypothesis.

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Optical and Magnetic Properties of Silica Implanted with N+ and Fe+

MRS Proceedings ◽

10.1557/proc-396-411 ◽

1995 ◽

Vol 396 ◽

Author(s):

T. Isobe ◽

R.A. Weeks ◽

R.A. Zuhr

Keyword(s):

Magnetic Field ◽

Relative Intensity ◽

Chemical Interaction ◽

Resonance Field ◽

Magnetic Interaction ◽

Atomic Ratio ◽

Resonance Absorption ◽

Iron Nitrides ◽

Optical And Magnetic Properties ◽

Different Doses

AbstractSilica platelets (Corning 7940) were implanted sequentially with N at 52 keV to different doses ranging from 0 to 1.2×l017 ions cm2 and then with Fe at 160 keV to a dose of 6×10 ions cm2. The optical absorption decreased with increasing N1 dose at photon energies ranging from 1.4 eV to 6.5 eV. The relative intensity, S(0°), of the ferromagnetic resonance absorption and its resonance field, H(0°), at θ = 0° were larger than S(90°) and H,(90°) at 0 = 90°, where Θ is the angle between the applied magnetic field and the normal to the implanted surface. The maximum values of S(0°) and S(90°) were observed near the N/Fe atomic ratio of 0.2. At the similar atomic ratio, the differential relative intensity, S(0°)- S(90°), and the differential resonance field, H,(0°)-H,(90°). associated with the degree of magnetic interaction between the produced compounds, also showed maxima. We conclude that sequential ion-implantation of N1 and Fe1 into silica causes a chemical interaction to produce iron nitrides.

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Exchangeable Ions

The Chemistry of Soils ◽

10.1093/oso/9780190630881.003.0013 ◽

2016 ◽

Author(s):

Garrison Sposito

Keyword(s):

Soil Analysis ◽

Metal Cations ◽

Alkaline Soils ◽

Charge Balance ◽

Surface Excess ◽

Acidic Soils ◽

Soil Humus ◽

Proton Charge ◽

Definition Of ◽

Particulate Soil

In Section 3.4, the cation exchange capacity, or CEC, of particulate soil humus is defined as the maximum number of moles of proton charge per kilogram that can be desorbed by a metal cation under prescribed conditions. Thus, CEC for particulate humus is equal to the maximum absolute value of the negative net proton charge. Operationally, this maximum value is measured typically as the surface excess of Ba2+ adsorbed by humus at pH 8.2 (Eq. 3.5). Extending this concept to soils, one can define the CEC as the maximum number of moles of readily exchangeablemetal cation charge per unit mass of dry soil that can be extracted under prescribed conditions. In this more general context, CEC refers to metal cations that adsorb on soil particles in either outer sphere surface complexes or the diffuse ion swarm (Fig. 7.2). In alkaline soils, the common readily exchangeable cations are Ca2+, Mg2+, Na+, and K+, whereas in acidic soils, this group expands to include Al3+, and its complexes AlOH2+, Al(OH)2+, and AlSO+4. Following the operational paradigm for soil humus, one concludes that the measurement of soil CEC involves not only the desorption of protons, but also the replacement of the population of readily exchangeable adsorbed metal cations at a selected pH value (usually pH 7–8) by a chosen cation. Laboratory procedures for measuring CEC are described in Methods of Soil Analysis, listed in For Further Reading at the end of this chapter. In alkaline soils, the replacing cation chosen is often Na+ or Ca2+, whereas in acidic soils and for soil humus, the replacing cation of choice is Ba2+. These cations, in turn, are typically displaced from soil particle surfaces by Mg2+ to measure the surface excess. A conceptual definition of CEC can be developed in terms of the surface charge balance concepts introduced in Chapter 7. Consider first a soil in which a net positive surface excess of anions does not occur, such as the Mollisol example discussed in Section 8.1. In this case, the only adsorbed ions are Ca2+ and Cl-. The CEC of this soil may be defined by a special case of the charge-balance condition in Eq. 7.3a: ∆qex (max) ≡ CEC

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IX. Nucleinsäuregehalt und Nucleinsäuresynthese nach Röntgenbestrahlung

Zeitschrift für Naturforschung B ◽

10.1515/znb-1966-1011 ◽

1966 ◽

Vol 21 (10) ◽

pp. 960-966 ◽

Cited By ~ 6

Author(s):

Yasuhiko Takamori ◽

Ernst-Randolf Lochmann ◽

Wolfgang Laskowski

Keyword(s):

Ribosomal Rna ◽

Rna Synthesis ◽

Small Difference ◽

Dry Weight ◽

Nucleic Acid Content ◽

X Rays ◽

X Ray ◽

Dna And Rna ◽

High Doses ◽

Different Doses

The amount of DNA and RNA per dry weight as well as the rate of RNA synthesis was determined in a series of almost isogenic and homozygous Saccharomyces strains of different ploidy which had irradiated with different doses of X-rays.It was found that the RNA content per dry weight showed only a small decrease after irradiation even with high doses. The decrease in the DNA content after irradiation is larger, and it is already maximal at the smallest X-ray dose tested (75 krad) . No further decrease could be observed even after application of 225 krad.The RNA synthesis is much more radioresistant in all strains tested (haploid-hexaploid) than the colony forming ability. X-ray doses which reduce the colony forming ability of the cells to less than 1% lead to a reduction of the RNA synthesis of only about 50 per cent. The inactivation of RNA synthesis increases with increasing irradiation doses and increasing incubation time after irradiation.There was only a small difference in the radiosensitivity of the synthesis of soluble or ribosomal RNA.Genetic effects on the radiation inactivation of the colony forming ability, previously described as “aα-effect” and “AS-effect”, show no influence on the radiosensitivity of cellular nucleic acid content and synthesis.

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Productive and Physiological Response of Organic Potato Grown under Highly Calcareous Soils to Fertilization and Mycorrhization Management

Agronomy ◽

10.3390/agronomy10081200 ◽

2020 ◽

Vol 10 (8) ◽

pp. 1200

Author(s):

Sara Lombardo ◽

Cristina Abbate ◽

Gaetano Pandino ◽

Bruno Parisi ◽

Aurelio Scavo ◽

...

Keyword(s):

Organic Farming ◽

Mycorrhizal Fungi ◽

Calcareous Soils ◽

Arbuscular Mycorrhizal ◽

Low Fertility ◽

Soil Conditions ◽

Alkaline Soils ◽

Gas Exchange Parameters ◽

Marketable Yield ◽

Potato Growth

The enhancement of the actual low yields is the most important challenge regarding organic farming management. In this view, a valid tool may arise by the improvement of fertilization management and efficiency. In this regard, arbuscular mycorrhizal fungi (AMF) can play an important role, especially in low fertility soils such as calcareous ones, through a better nutrient uptake and by alleviating abiotic stresses. A replicated-space experiment was carried out to investigate the role of mycorrhizal-based inoculants combined with full or halved fertilizer doses on yield and physiological traits of three early potato cultivars organically grown in highly calcareous and alkaline soils. The results indicate that AMF symbiosis ameliorated, in comparison to the not-inoculated plants, the potato tolerance to limestone stress by enhancing the potential quantum efficiency of photosystem II (Fv/F0) and plant gas-exchange parameters (photosynthesis rate and stomatal conductance). Moreover, a significant improvement of marketable yield (+25%) was observed, mainly due to an increase of the number of tubers plant−1 (+21%) and, to a lesser extent, of average tuber weight (+10%). The AMF efficiency was higher applying halved fertilizer doses and in the location where soil conditions were unfavourable for potato growth. Moreover, the qRT-PCR highlighted that AMF colonization was similar in each location, demonstrating their tolerance to limestone, alkalinity and P stresses. These findings outlined that AMF are good candidate to bio-ameliorate calcareous soils and are very useful for improving potato yields under organic farming, limiting external fertilizers supply and environmental pollution.

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Lime chlorosis and other factors affecting the distribution of Eucalyptus on coastal sands in Southern Australia

Australian Journal of Botany ◽

10.1071/bt9670095 ◽

1967 ◽

Vol 15 (1) ◽

pp. 95 ◽

Cited By ~ 12

Author(s):

RF Parsons ◽

RL Specht

Keyword(s):

Growth Rate ◽

Growth Rates ◽

The Other ◽

Alkaline Soils ◽

Acidic Soils ◽

Calcareous Sand ◽

Factors Affecting ◽

Physiological Tolerance ◽

Calcareous Sands ◽

Beach Sands

In southern Australia, deep calcareous and deep siliceous sands each carry a distinctive assemblage of eucalypts. Three of these species with contrasting edaphic ranges were investigated: Eucalyptus baxteri, which is widespread on acidic soils and is never found on highly alkaline soils like the calcareous sands; E. incrassata, which is widespread on acidic and neutral soils, occurs occasionally on some highly alkaline soils, but is also absent from calcareous beach sands; and E. diversifolia, which is found on both acidic and highly alkaline soils and is widespread on calcareous beach sands. All three species occur on siliceous sands, with E. baxteri in wetter areas than the other two species. Comparative pot experiments in which typical calcareous and siliceous sands were used showed that: (1) E. baxteri is stunted by severe lime chlorosis when grown on calcareous sand, while the other two species are not affected. (2) E. baxteri markedly outyields the other two species on siliceous sands. It is suggested that E. baxteri is absent from calcareous sands because it is physiologically intolerant of highly alkaline soils, and that E. baxteri replaces the other two species on the wetter siliceous sands because its faster growth rate enables it to outcompete them when rainfall is adequate. However, the slower growth rates of E. diversifolia and E. incrassata will be accompanied by slower rates of water use and this may give them an advantage over E. baxteri on drier siliceous sands. The wide edaphic range of E. diversifolia is considered to be the outcome of the wide physiological tolerance of individual plants rather than of intraspecific differentiation.

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