Soil organic carbon (SOC) and mineral nitrogen (Nmin), especially nitrates (NO3−) in agroecosystems have attracted much attention over the past few decades due to their crucial roles in soil ...fertility, crop productivity, environmental quality, and/or climate change mitigation and adaptation. The aim of the study was to evaluate the contents of organic carbon, ammonium, and nitrate in soils under differentiated pH, texture, and fertilization rates. A large-scale environmental study was conducted in Polish arable lands. The spatial distribution of the sampling points reflected agricultural production conditions, variability of soil properties, and representativeness of textures that are characteristic of Poland. Our results indicated that SOC content was significantly affected by the soil pH and texture as well as mineral and organic fertilization. The same factors, except organic amendments, significantly supported mineral nitrogen concentration in the present study. The most important factors controlling SOC in the study were ranked as follows: soil pH > pre-crop N fertilization > crop N fertilization > N applied with manure > soil texture. In the case of N-NH4 and N-NO3, mineral fertilization was the most critical variable. The carbon and nitrogen governance in agroecosystems should consider the ranks of factors controlling their contents.
This study assessed the possibility of using iodine-containing fertilizers for agronomic biofortification of rye biomass used as fodder for cows, and establish the best application method and form ...and the optimal dose of iodine (I) under field conditions. The impact of iodine fertilization on grain iodine content was not studied. Results showed that agronomic biofortification of rye plants with iodine, influenced by its dose, form, and method of application was highly effective in increasing I shoot contents. Plant I-enrichment via foliar and soil application significantly affected I concentration in plant biomass even at a low dose (2.5 kg ha
). Soil I application as KI appeared optimal for rye plants used as fodder for cows, especially cropped under the soil with a neutral reaction. Iodine application improved the biological quality of rye plants by increasing concentrations of sugar, chlorophylls, and at a low rate, protein and total antioxidant capacity.
•Due to climate change the surface of floodplain water bodies decreases substantially.•The share of small lakes and ponds increases.•Small floodplain lakes may be a substantial source of CO2 ...emission.•Carbon is buried mostly in insoluble forms.
Small floodplain lakes (SFLs), characterized by their diminutive size (<10,000 m2), have been consistently overlooked in assessments of organic carbon (C) stock and the impacts of climate changes. This study aims to ascertain both the quantity and quality of carbon stored within the sediments of SFLs. Furthermore, we endeavour to evaluate the influence of ongoing climate change on the floodplain lake structure within the continental humid climate zone on the example of the Vistula River valley and estimate the CO2 emission from dry floodplain lakes. The sedimentary organic carbon content (TOC) ranged from 2.3–64 g kg−1, averaging at 3.4 g kg−1. Consequently, the sediments in the analysed SFLs of the river section potentially harbour up to 5,785 Mg TOC. Notably, the abundance of easily soluble carbon fractions (humic and fulvic acids) was relatively low (∼15 %), implying a stable immobilization of organic C compounds and minimal impact of sediments on water quality. Satellite imagery analysis for the years 2017–2020 revealed a 31 % reduction in the total lake surface area within a 100-km-long segment of the Vistula River. The decreasing surface area of floodplain lakes and rising mean air temperatures increase CO2 emissions and have an additional impact on climate warming. Our research underscores that investigating lake C storage concerning climate change demands a nuanced approach. While higher temperatures stimulate primary production, the reduction in lake surface area and the escalating role of small lakes, such as SFLs, in C storage should be paramount considerations.
Carbon and nitrogen compounds in agroecosystems have attracted much attention in recent years due to their key roles in crop production and their impacts on environment quality and/or climate change. ...Since fertilization profoundly disrupted the C and N cycles, several mitigation and/or adaptation strategies, including the application of farmyard manure (FYM) and/or urease and nitrification inhibitors (UI and NI), have been developed. The aim of this study was to evaluate the contents of soil organic carbon and its fractions, the total and mineral forms of nitrogen, as well as CO2 and N2O emissions under mineral and organic fertilization with and without urease and nitrification inhibitors in a maize agroecosystem. A two-year field study was carried out on Cambisols (silt) in Poland. The experiment scheme included nine treatments: C (the control without fertilization), UAN (Urea Ammonium Nitrate), UAN+UI, UAN+NI, UAN+UI+NI, FYM with N mineral fertilizer base, FYM with N mineral fertilizer base+UI, FYM with N mineral fertilizer base+NI, and FYM with N mineral fertilizer base+UI+NI. It was found that treatments fertilized with cattle FYM were higher sinks and sources of C and N compounds in comparison to the UAN plots. The organic carbon, humic and humin acid, and total nitrogen concentrations, in contrast to ammonium and nitrate nitrogen, were not affected by the inhibitors added. Nitrification and urease inhibitors were effective in decreasing N2O emissions only in treatments that were exclusively applied with UAN and had no significant influence on CO2 emissions.
Soil acidification in agroecosystems is a natural process that could be accelerated, mainly by the inappropriate application of mineral fertilizers, or prevented, by sustainable management practices. ...On the basis of a three-year field study in a grassland agroecosystem, the impact of different rates of fertilization with nitrogen (N), phosphorus (P), and potassium (K) on soil chemical parameters related to soil acidity was evaluated. It was found that high-rate fertilization with ammonium nitrate accelerated the soil acidification process, which was additionally intensified by the application of superphosphate and potassium salt. The sum of exchangeable base cations, the values of base saturation and hydrolytic acidity in the soil reflected the interactions between the applied NPK-fertilizer levels. Considering chemical parameters related to soil acidity studied in this experiment, it seems that the best strategies for mitigating soil acidification in grasslands are reducing nitrate leaching, changing fertilizer types and increasing the input of base cations.
IMPORTANCE: Intraoperative handovers of anesthesia care are common. Handovers might improve care by reducing physician fatigue, but there is also an inherent risk of losing critical information. ...Large observational analyses report associations between handover of anesthesia care and adverse events, including higher mortality. OBJECTIVE: To determine the effect of handovers of anesthesia care on postoperative morbidity and mortality. DESIGN, SETTING, AND PARTICIPANTS: This was a parallel-group, randomized clinical trial conducted in 12 German centers with patients enrolled between June 2019 and June 2021 (final follow-up, July 31, 2021). Eligible participants had an American Society of Anesthesiologists physical status 3 or 4 and were scheduled for major inpatient surgery expected to last at least 2 hours. INTERVENTIONS: A total of 1817 participants were randomized to receive either a complete handover to receive anesthesia care by another clinician (n = 908) or no handover of anesthesia care (n = 909). None of the participating institutions used a standardized handover protocol. MAIN OUTCOMES AND MEASURES: The primary outcome was a 30-day composite of all-cause mortality, hospital readmission, or serious postoperative complications. There were 19 secondary outcomes, including the components of the primary composite, along with intensive care unit and hospital lengths of stay. RESULTS: Among 1817 randomized patients, 1772 (98%; mean age, 66 SD, 12 years; 997 men 56%; and 1717 97% with an American Society of Anesthesiologists physical status of 3) completed the trial. The median total duration of anesthesia was 267 minutes (IQR, 206-351 minutes), and the median time from start of anesthesia to first handover was 144 minutes in the handover group (IQR, 105-213 minutes). The composite primary outcome occurred in 268 of 891 patients (30%) in the handover group and in 284 of 881 (33%) in the no handover group (absolute risk difference RD, −2.5%; 95% CI, −6.8% to 1.9%; odds ratio OR, 0.89; 95% CI, 0.72 to 1.10; P = .27). Nineteen of 889 patients (2.1%) in the handover group and 30 of 873 (3.4%) in the no handover group experienced all-cause 30-day mortality (absolute RD, −1.3%; 95% CI, −2.8% to 0.2%; OR, 0.61; 95% CI, 0.34 to 1.10; P = .11); 115 of 888 (13%) vs 136 of 872 (16%) were readmitted to the hospital (absolute RD, −2.7%; 95% CI, −5.9% to 0.6%; OR, 0.80; 95% CI, 0.61 to 1.05; P = .12); and 195 of 890 (22%) vs 189 of 874 (22%) experienced serious postoperative complications (absolute RD, 0.3%; 95% CI, −3.6% to 4.1%; odds ratio, 1.02; 95% CI, 0.81 to 1.28; P = .91). None of the 19 prespecified secondary end points differed significantly. CONCLUSIONS AND RELEVANCE: Among adults undergoing extended surgical procedures, there was no significant difference between the patients randomized to receive handover of anesthesia care from one clinician to another, compared with the no handover group, in the composite primary outcome of mortality, readmission, or serious postoperative complications within 30 days. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04016454
In this paper, we propose several solutions to the committee selection problem among participants of a DAG distributed ledger. Our methods are based on a ledger intrinsic reputation model that serves ...as a selection criterion. The main difficulty arises from the fact that the DAG ledger is a priori not totally ordered and that the participants need to reach a consensus on participants' reputation. Furthermore, we outline applications of the proposed protocols, including: (i) self-contained decentralized random number beacon; (ii) selection of oracles in smart contracts; (iii) applications in consensus protocols and sharding solutions. We conclude with a discussion on the security and liveness of the proposed protocols by modeling reputation with a Zipf law.
The security of any Distributed Ledger Technology (DLT) depends on the safety of the network layer. Much effort has been put into understanding the consensus layer of DLTs. However, many network ...layer designs seem ad-hoc and lack a careful analysis of the influence of the design decisions on the whole DLT system. We propose a salt-based automated neighbor selection protocol that shows the inherent tradeoffs of certain design decisions and allows a quantitative treatment of some network topology requirements. This example may serve as a design framework and facilitate future research. We provide a selection of results from simulations to highlight some tradeoffs in the design decisions.
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