This study evaluates the potential of manure-derived biochars in promoting plant growth and enhancing soil chemical and biological properties during a 150day pot experiment. Biochars from pyrolysis ...of poultry litter (PL) and swine manure (SM) at 400 and 600°C, and a commonly available wood chip (WC) biochar produced at high temperature (1000°C) were incorporated to silt-loam (SL) and sandy (SY) soils on a 2% dry soil weight basis. Ryegrass was sown and moisture was adjusted to 60% water filled pore space (WFPS). The PL400 and SM400 biochars significantly increased (p<0.05) shoot dry matter (DM) yields (SL soil) and enhanced nitrogen (N), phosphorus (P) and potassium (K) uptake by the plants in both soils, compared to the Control. All biochars significantly increased the soil carbon (C) contents compared to the Control. Total N contents were significantly greater for PL400 and PL600 treatments in both soils. The dehydrogenase activity (DA) significantly increased for PL400 and SM400 treatments and was positively correlated with the volatile matter (VM) contents of the biochars, while β-glucosidase activity (GA) decreased for the same treatments in both soils. All biochars significantly shifted (p≤0.05) the bacterial community structure compared to the Control. This study suggests that pyrolysis of animal manures can produce a biochar that acts as both soil amendment and an organic fertilizer as proven by increased NPK uptake, positive liming effect and high soil nutrient availability, while WC biochar could work only in combination with fertilizers (organic as well as mineral).
Picture 1 Graphical abstract highlighting “Chemically and biologically-mediated fertilizing value of manure-derived biochars”. Display omitted
•Low temperature manure biochars enhanced DM yield, NPK uptake, and soil properties.•More positive effects of biochars on acidic silt-loam than on alkaline sandy soil.•Wood biochar had no effect on DM yield but showed a good C sequestration potential.•All biochars shifted bacterial community structure and modified enzyme activities.
Why should a parcel of agricultural land be abandoned when there is a scarcity of food? In this paper, we address this question in relation to the hills of Nepal, where agricultural land is being ...abandoned at an unprecedented rate, despite looming food scarcity. Responding to studies that have highlighted land abandonment trends, we conducted in-depth case studies in two of Nepal's hill districts to understand how land abandonment is taking place, and under what circumstances. Using an interdisciplinary lens and transcending linear models of agrarian change which attribute land abandonment to one or more prominent factors, our study unravels complex, cross-scalar processes, involving the interaction among social forces and environmental factors which lead to land underutilisation. The paper shows that land underutilisation happens through what we term ‘socio-environmental pathways’, which operate across scales, yet are deeply rooted in local dynamics of agrarian change. These pathways are triggered by, and embroiled within, three wider socio-economic and political dynamics in contemporary Nepal, namely: socio-cultural changes that favour out-migration; evolving economic opportunities that make farming less profitable; and a policy context in which the gravity of the land abandonment challenge goes unrecognised. The framework of ‘socio-environmental pathways’ applied here also advances a theoretical lens to explain agrarian change in a way that integrates multiple scales and multiple sectors, emphasising a thoroughly empirical approach. Finally, we identify key policy implications of this research on livelihoods and sustainable development.
•Despite looming food insecurity, agricultural land underutilisation is happening in the Nepal hills.•Land underutilisation results from the interplay of social, economic, cultural, political and environmental factors.•A conceptual framework of socio-environmental pathways is developed and applied to analyse land underutilisation.•Local land management decisions are shaped by external processes – such as national politics and overseas youth migration.•Socio-environmental pathways lens helpful in understanding and responding to agrarian change.
Airy light-sheet Raman imaging Subedi, N R; Yaraghi, S; Jung, P S ...
Optics express,
09/2021, Letnik:
29, Številka:
20
Journal Article
Recenzirano
Odprti dostop
Light-sheet fluorescence microscopy has greatly improved the speed and overall photostability of optically sectioning cellular and multi-cellular specimens. Similar gains have also been conferred by ...light-sheet Raman imaging; these schemes, however, rely on diffraction limited Gaussian beams that hinder the uniformity and size of the imaging field-of-view, and, as such, the resulting throughput rates. Here, we demonstrate that a digitally scanned Airy beam increases the Raman imaging throughput rates by more than an order of magnitude than conventional diffraction-limited beams. Overall, this, spectrometer-less, approach enabled 3D imaging of microparticles with high contrast and 1 µm axial resolution at 300 msec integration times per plane and orders of magnitude lower irradiation density than coherent Raman imaging schemes. We detail the apparatus and its performance, as well as its compatibility with fluorescence light-sheet and quantitative-phase imaging towards rapid and low phototoxicity multimodal imaging.
For more than three decades, the remote sensing scientific community has successfully generated predictive models of tropical forest attributes and ecological processes at the leaf, canopy, patch ...and landscape scale by linking field-measured data to remotely sensed spectral values, as well as other variables derived from remotely sensed data. The main interest of these applications is to help describe ecological and functional patterns occurring at larger geographic scales with sufficient accuracy and precision and enable scientists to better understand ecological processes, such as the relationship between atmospheric fluxes, plant structural and ecophysiological traits, soil attributes, anthropogenic use, species occurrence and animal movement. However, as the earth’s environment suffers from ever-increasing human use and abuse, detecting spatiotemporal changes in these variables has become a necessary decision-making tool in conservation action and natural resources’ management. Moving from modeling into the study of soil, plants, wildlife and socioecological processes using remotely sensed data requires the extrapolation of single time-step models to its application on a time series of data with the same expected accuracy. The challenges in this matter are not trivial, since changes in soil moisture conditions, cloud contamination, canopy and leaf-level geometry and physiology can affect the strength of the proposed models. In this context, the term ‘Operationalization’ refers to migration from single time-step models to time series but also refers to the design and implementation of user-friendly tools to increase the efficacy of communicating spatiotemporal trends to the users. ...
The urgency to preserve tropical forest remnants has encouraged the development of remote sensing tools and techniques to monitor diverse forest attributes for management and conservation. ...State-of-the-art methodologies for mapping and tracking these attributes usually achieve accuracies greater than 0.8 for forest cover monitoring; r-square values of ~0.5–0.7 for plant diversity, vegetation structure, and plant functional trait mapping, and overall accuracies of ~0.8 for categorical maps of forest attributes. Nonetheless, existing operational tropical forest monitoring systems only track single attributes at national to global scales. For the design and implementation of effective and integrated tropical forest monitoring systems, we recommend the integration of multiple data sources and techniques for monitoring structural, functional, and compositional attributes. We also recommend its decentralized implementation for adjusting methods to local climatic and ecological characteristics and for proper end-user engagement. The operationalization of the system should be based on all open-source computing platforms, leveraging international support in research and development and ensuring direct and constant user engagement. We recommend continuing the efforts to address these multiple challenges for effective monitoring.
Combining amendments to the soil made by biochar or hydrochar with nitrogen (N) fertilizer can modify soil N dynamics and availability. Such a response suggests that these amendments would affect ...ammonia (NH₃) emissions from slurry similarly, and potentially reduce volatilization of NH₃. This study measured the potential emissions of NH₃ following application of pig slurry to the surface of silt‐loam and loam soils amended with biochar and hydrochar (both derived from Miscanthus × giganteus (Greef et Deu)) at a rate of 3% soil dry weight (16 t ha⁻¹ soil area, on average) and 60% water‐filled pore space (WFPS). The experiment was carried out in a dynamic chamber connected to a photo‐acoustic trace gas analyser in a controlled climate (20°C) for 48 hours. Statistically significant differences (P < 0.05) in total emissions were observed between both treatment and soil types. Surprisingly, both amendments increased emissions of NH₃ compared with the control; cumulative NH₃ emissions averaged 38.7 and 23.5% of applied total ammonium nitrogen (TAN) for hydrochar and biochar, respectively, whereas it was 18.2% for the control. The larger emissions in hydrochar‐amended soil were attributed to the reduced ability to absorb NH₄ ⁺ associated with greater hydrophobicity and strong pH buffering of the slurry. Furthermore, final soil analyses with deionised water extracts showed significant differences (P < 0.05) in mineral N concentration between treatments. The smaller ammonium concentrations in biochar‐amended soil suggest that some NH₄ ⁺‐N was immobilized by adsorption on to biochar surfaces. This study observed that biochar and hydrochar properties, as well as soil characteristics, play important roles in controlling NH₃ emissions from surface slurry applications. The results obtained identified circumstances where these amendments even enhance volatilization, which provides new information on and insight into the extent and limitations of the potential of biochar and hydrochar for the mitigation of emissions.
Since its first demonstration over 100 years ago, scattering‐based light‐sheet microscopy has recently re‐emerged as a key modality in label‐free tissue imaging and cellular morphometry; however, ...scattering‐based light‐sheet imaging with subcellular resolution remains an unmet target. This is because related approaches inevitably superimpose speckle or granular intensity modulation on to the native subcellular features. Here, we addressed this challenge by deploying a time‐averaged pseudo‐thermalized light‐sheet illumination. While this approach increased the lateral dimensions of the illumination sheet, we achieved subcellular resolving power after image deconvolution. We validated this approach by imaging cytosolic carbon depots in yeast and bacteria with increased specificity, no staining, and ultralow irradiance levels. Overall, we expect this scattering‐based light‐sheet microscopy approach will advance single, live cell imaging by conferring low‐irradiance and label‐free operation towards eradicating phototoxicity.
Scattering‐based light‐sheet microscopy, a more than 100 years old microscopy technique, has recently re‐emerged as a key label‐free tissue imaging method. Here, we present an advancement of this method that enables both subcellular resolution and low levels of irradiance. We validated this approach by imaging carbon deposits in yeast and bacteria (Figure) with increased specificity and no staining.
Figure: PHB granule imaging in Methylobacterium extorquens by light‐sheet scattering and fluorescence.
Reducing water requirements and lowering environmental footprints require attention to minimize risks to food security. The present study was conducted with the aim to identify appropriate root ...traits enhancing rice grain yield under alternate wetting and drying conditions (AWD) and identify stable, high-yielding genotypes better suited to the AWD across variable ecosystems. Advanced breeding lines, popular rice varieties and drought-tolerant lines were evaluated in a series of 23 experiments conducted in the Philippines, India, Bangladesh, Nepal and Cambodia in 2015 and 2016. A large variation in grain yield under AWD conditions enabled the selection of high-yielding and stable genotypes across locations, seasons and years. Water savings of 5.7-23.4% were achieved without significant yield penalty across different ecosystems. The mean grain yield of genotypes across locations ranged from 3.5 to 5.6 t/ha and the mean environment grain yields ranged from 3.7 (Cambodia) to 6.6 (India) t/ha. The best-fitting Finlay-Wilkinson regression model identified eight stable genotypes with mean grain yield of more than 5.0 t/ha across locations. Multidimensional preference analysis represented the strong association of root traits (nodal root number, root dry weight at 22 and 30 days after transplanting) with grain yield. The genotype IR14L253 outperformed in terms of root traits and high mean grain yield across seasons and six locations. The 1.0 t/ha yield advantage of IR14L253 over the popular cultivar IR64 under AWD shall encourage farmers to cultivate IR14L253 and also adopt AWD. The results suggest an important role of root architectural traits in term of more number of nodal roots and root dry weight at 10-20 cm depth on 22-30 days after transplanting (DAT) in providing yield stability and preventing yield reduction under AWD compared to continuous flooded conditions. Genotypes possessing increased number of nodal roots provided higher yield over IR64 as well as no yield reduction under AWD compared to flooded irrigation. The identification of appropriate root architecture traits at specific depth and specific growth stage shall help breeding programs develop better rice varieties for AWD conditions.
Key Clinical Message
Patients mimicking appendicitis symptoms in a rural setting or those post‐appendectomy, indicating cecal volvulus, should always be considered. Swift action can prevent ...catastrophic consequences.
We present a case of a 14‐year‐old female who initially underwent open appendectomy for acute appendicitis and subsequently experienced symptoms of abdominal distention, vomiting, and fever. Her condition deteriorated following the appendectomy, despite a prior appendectomy for similar symptoms at a different facility. A computed tomography (CT) scan identified cecal volvulus as the underlying issue. This led to the performance of a laparotomy, cecopexy, and decompressive ileostomy. After six weeks, ileostomy closure was successfully carried out, and the patient currently enjoys good health. This case highlights the significance of considering uncommon factors as potential contributors to postoperative complications in young patients.
Abstract Corynebacterium ulcerans is an important zoonotic pathogen which is causing diphtheria-like disease in humans globally. In this study, the genomes of three recently isolated C. ulcerans ...strains, 4940, 2590 and BR-AD 2649, respectively from an asymptomatic carrier, a patient with pharyngitis and a canine host, were sequenced to investigate their virulence potential. A comparative analysis was performed including the published genome sequences of 16 other C. ulcerans isolates. C. ulcerans strains belong to two lineages; 13 strains are grouped together in lineage 1, and six strains comprise lineage 2. Consistent with the zoonotic nature of C. ulcerans infections, isolates from both the human and canine hosts clustered in both the lineages. Most of the strains possessed spaDEF and spaBC gene clusters along with the virulence genes cpp , pld , cwlH , nanH , rpfI , tspA and vsp1 . The gene encoding Shiga-like toxin was only present in one strain, and 11 strains carried the tox gene encoding the diphtheria-like toxin. However, none of strains 4940, 2590 and BR-AD 2649 carried any toxin genes. These strains varied in the number of prophages in their genomes, which suggests that they play an important role in introducing diversity in C. ulcerans. The pan-genomic analyses revealed a variation in the number of membrane-associated and secreted proteins that may contribute to the variation in pathogenicity among different strains.
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