bluuebunny/crossref_metadata_2025 huggingface dataset:
Efecto de inoculación micorrízica arbuscular combinada con fertilización nitrogenada en el pasto saboya (Megathyrsus maximus)
Authors:   Universidad Técnica de Manabí, Zambrano Velasquez Jimmy Ivan , de Jesús Peña Manuel ,   Escuela Superior Politécnica Agropecuaria de Manabí Manuel Félix López, ubicada en el km 2.7 vía Calceta-El Morro-El Limón, Vera Saldarriaga Hilder Enrique ,   Universidad Técnica de Manabí, Sitio Las Ánimas Km 2½ vía Chone-Boyacá
Published: June 2021

La presente investigación es una revisión bibliográfica que tiene por objetivo examinar el efecto de la inoculación micorrízica arbuscular combinada con la fertilización nitrogenada sobre el pasto Saboya (Megathyrsus maximus). Para sustentar teóricamente este estudio se analizaron 80 artículos obtenidos mediante Google Académico a través de fuentes primarias como investigaciones originales, tesis de grado, de maestría; y de fuentes secundarias extraídas de bases de datos como Dialnet, Redalyc y Scielo, asimismo para la búsqueda bibliográfica se determinó palabras clave pasto Saboya (Megathyrsus maximus), fertilización nitrogenada, inoculación micorrízica arbuscular y uso combinado de fertilización nitrogenada e inoculación micorrízica arbuscular. Se concluyó que la inoculación de hongos micorrízicos arbusculares conjuntamente con la fertilización nitrogenada sobre el pasto Saboya constituye una opción válida para optimizar la absorción de minerales y nutrientes de este género mejorando su rendimiento y calidad, lo cual favorece el perfil alimentario del ganado en el cantón Chone y el país. Se evidenció que, en este sentido, el desafío más importante para el Ecuador es fomentar líneas investigativas dirigidas a implementar ambos métodos de fertilización para alcanzar elevados índices de productividad del pasto Saboya, tomando en cuenta factores como el tipo de suelo, la selección de cepas eficientes y el manejo de cantidades de fertilizante nitrogenado acordes a las necesidades reales del suelo.
Caracterización y temporalidad de enemigos naturales de Opsiphanes cassina en palma aceitera, estado Monagas, Venezuela
Authors:   Instituto Nacional de Investigaciones Agrícolas, Centro de Investigaciones Agrícolas del estado Monagas. Apartado Postal 184. Z.P. 6201. Maturín, Monagas, Venezuela, Rodríguez Gonzalez Gladys , Silva-Acuña Ramón ,   Universidad de Oriente, Núcleo de Monagas, Escuela de Ingeniería Agronómica, Postgrado de Agricultura Tropical, Maturín, Venezuela, Cásares Moizant Rafael ,   Instituto de Zoología Agrícola, Facultad de Agronomía, Universidad Central de Venezuela, Apartado Postal 4579. Z.P.2101-A. Maracay, Aragua, Venezuela, Díaz Quintana Asdrúbal ,   Instituto Nacional de Investigaciones Agrícolas, Centro de Investigaciones Agrícolas del estado Monagas. Apartado Postal 184. Z.P. 6201. Maturín, Monagas, Venezuela, Barrios Maestre Renny ,   Instituto Nacional de Investigaciones Agrícolas, Centro de Investigaciones Agrícolas del estado Monagas. Apartado Postal 184. Z.P. 6201. Maturín, Monagas, Venezuela
Published: June 2021

La investigación se condujo con el objetivo de realizar la caracterización y temporalidad de los enemigos naturales asociados con Opsiphanes cassina en una plantación de palma aceitera, ubicada en el estado Monagas, Finca “El Águila” Venezuela. Se efectuaron evaluaciones a intervalos semanales, durante el ciclo agosto 2015/agosto 2016, seccionando la hoja número 25 de dos plantas.ha-1 en un lote de 10 ha. Se cuantificó el número de huevos, larvas diferentes instares y pupas, así como también, de sus enemigos naturales y las especies vegetales que les ofrecen alimento y refugio dentro del área experimental. Los agentes de control biológico identificados correspondieron a Telenomus sp. (Scelionidae), Anastatus sp. (Eupelmidae) y un eulófido como parasitoides de huevos; Cotesia sp. (Braconidae) de larvas del V instar y Conura maculata F (Chalcididae) de pupas. Cotesia sp., fue el entomófago más relevante en la regulación de las poblaciones del insecto. La presencia de especies como Croton trinitatis Mills y Solanum hirtum L favorecen el fortalecimiento del control biológico natural de O. cassina.
ALGORITHMS OF SYSTEM SYNTHESIS FOR STABILIZING UNCERTAIN DYNAMIC OBJECTS
Authors:   Tashkent State Technical University, Mamirov Uktam
Published: June 2021

The article deals with the formation of stable algorithms for the system synthesis for the stabilizing uncertain dynamic objects based on the method of local optimization in the presence of approximate mathematical models. The article analyzes the issues of building adaptive control systems using the concept of roughness, taking into account the assessment of the maximum allowable discrepancy between the object and its model. Some of the most constructive algorithms for determining pseudo-inverse matrices are given. When calculating the pseudo-inverse matrix of the control object, modified QR decomposition algorithms are used, obtained by deleting or assigning a column. The obtained algorithms allow us to conclude that the stabilization systems can be built on the basis of the local optimization method in the presence of approximate mathematical models. At the same time, it turns out that the asymptotic stability, i.e., the limited output with a limited input, can be achieved with sufficiently rough estimates of the object parameters and external perturbations using regular methods.
PRINCIPLES OF ELIMINATING THE IMPACT OF DISTURBANCES ON INTEGRATED INFORMATION AND ANALYTICAL SYSTEMS
Authors:   Tashkent State Technical University, Zaripov Oripjon , Khamrakulov Umidjon , Isxakova Fatima
Published: June 2021

Today, production management using integrated information and analytical systems and their integration with the elements of Industry 4.0 is considered one of the most pressing problems in all areas of production. The correct formation of the structure of information systems in their development contributes to the formation of elements of Industry 4.0 and their further full and high-quality integration into other areas. When implementing these processes, one of the most important steps is to reduce the impact of disturbances on integrated information and analytical systems. Taking into account the above, the article considers mathematical models of the principles of eliminating the influence of disturbances on integrated information and analytical systems. In addition, the optimal solutions for reducing the impact of disturbances on integrated information and analytical systems are presented
İlkokul 4. Sınıf Öğrencilerinin Çevre ve Alan Konularında Yaptıkları Hataların Analizi
Authors: DİVRİK Ramazan , PİLTEN Pusat
Published: June 2021

Çevre ve alan konuları öğrencilerin ilkokul yıllarında karşılaştığı birbiri ile sürekli karıştırılan iki konu arasında yer almaktadır. Bu yüzden ilkokul yıllarında çevre ve alan konularında öğrencilerin kullandığı çözüm stratejilerinin belirlenmesi; bu çözümlerde yapılan hataların tespit edilerek gereken önlemlerin alınması önemli görülmektedir. Bu amaçla, ilkokul 4. sınıf düzeyinde çevre ve alan konularında öğrencilerin kullandığı çözüm stratejilerinin belirlenmesi ve yapılan hataların analiz edilmesi bu çalışmanın amacını oluşturmaktadır. Araştırmada nitel araştırma desenlerinden durum çalışması deseni kullanılmıştır. Araştırmanın verileri 174 ilkokul dördüncü sınıf öğrencisinden toplanmış; verilerin analizinde betimsel analiz kullanılmıştır. Analiz safhasında ilk önce öğrencilerin sorulara vermiş oldukları cevapların doğruluk düzeyleri ve soruların çözümünde kullanılan stratejiler belirlenmiştir. Ardından öğrencilerin hatalı cevap kâğıtları üzerinden hata türleri belirlenerek analizler yapılmıştır. Araştırma sonucunda, çevre hesaplama sorularında formül kullanma, zihinden işlem yapma ve kenar uzunluklarını toplama stratejileri; alan hesaplama sorularında birim kareleri sayma, zihinden işlem yapma ve bütün parça ile taralı parça ilişkisini ele alma stratejilerinin kullanıldığı tespit edilmiştir. Çevre hesaplama sorularında en fazla işlem hatası, ne yapacağını bilmeme ve nasıl tanımlayacağını bilmeme hataları yapılmıştır. Alan hesaplama sorularında ise işlem hatası, geometrik şeklin yanlış modellenmesinden kaynaklanan hatalar ve nasıl tanımlayacağını bilmeme hataları yapılmıştır. Öğrencilerin yapmış olduğu bu hataların giderilmesinde, çevre ve alan kavramlarının öğretiminde öncelikle öğrencilerin kavramsal gelişimini destekleyici çalışmalarla derslerin yürütülmesi ve öğrencilerin geometrik şekillere ait çevre ve alan formüllerine kendilerinin ulaşması önerilmektedir.
Kur’ân’ın İ'câz Yönlerinden Biri: Gelecek ile İlgili Haber Vermesi
Authors: KAPLAN Abdurrahim
Published: June 2021

Kur’ân’ın nüzûl gayesi yeryüzünde tevhid inancını te’sis edip insanları dünya ve âhiret saadetine ulaştırmaktır. Bu gayeyi birtakım kural ve kaidelerle gerçekleştiren Kur’ân, bu süreçte en büyük vazifeyi peygamberlere vermiştir. Dinler tarihi ve mukaddes kitaplardaki bilgilere göre bütün peygamberler insanların karşısına mu’cizelerle çıkmışlardır. Peygamberlerin getirdikleri mu’cizeler, ilâhî bir kudrete dayanan, insan gücünün üstündeki olaylardır. Hz. Muhammed de her peygamber gibi birtakım mu’cizelerle insanların karşısına çıkmıştır. Onun en büyük mu’cizesi ise kendisine inzâl olunan Kur’ân’dır. Kur’ân’da yer alan mu’cizelerin bir kısmı insanların his ve duygularına hitap ederken diğer bir kısmı ise onların akıl, fikir ve mantığına hitap etmektedir. Kur’ân’ın i’câz yönü daha çok dil konusuna ve geleceğe yönelik olarak ilmî konulara yöneliktir. Kur’ân; düşünen, akıl sahibi olan insanların, ibret, hikmet, öğüt ve benzeri mu’cize ifade eden bilgilerden faydalanmalarını talep etmektedir. Çünkü kişi akıl ve düşüncesini harekete geçirmekle doğrulara ulaşabilmektedir. Bu da Kur’ân’ın mu’cizelerle dolu olduğunu ortaya koymaktadır. Kur’ân’daki mu’cizeler konusunda çalışmalarda bulunan âlimler, kendilerine göre tasnifler yapmış ve yorumlarda bulunmuşlardır. Telif edilen bu çalışmalarda Kur’ân’ın; dil ve belagat yönünden i’câzı, ilmî i’câzı, geçmiş ve gelecekten haber verme yönünden i’câzı, ortaya koyduğu insan hak ve hukuku istikametindeki i’câzı ve benzeri konularda çeşitli görüşler ileri sürülmüş, bu konularda açıklamalar yapılmıştır. Biz ise bu çalışmada gelecekten haber verme yönünden Kur’ân’ın i’câzı üzerinde durmaya çalışacağız.
Taloustieteen performatiivisuudesta moniperformatiivisuuteen
Authors: Tiikkainen Olli , Virtanen Mikko J.
Published: June 2021

Toimijaverkostoteoreetikko Michel Callonin ajattelusta liikkeelle lähtenyt performatiivisuuden tutki-musohjelma on kahden viime vuosikymmenen aikana saavuttanut merkittävän aseman taloutta tarkastelevan yhteiskuntatieteen kentällä. Ohjelma on kohdannut viime vuosina kuitenkin myös kritiikkiä sen tavasta tarkastella taloudellisia ilmiöitä ensisijaisesti yhdestä suunnasta, talouden tiedekytkennän kautta. Osallistumme artikkelillamme tähän Callonin tutkimusohjelman päivittämisestä käytävään keskusteluun: Avaamme ensin ohjelman ydinsisältöjä ja pureudumme sille rakentuviin tapaustutkimuksiin, joiden kohteena on yksi vastuullisen liiketoiminnan uusimmista muodoista, vaikuttavuusinvestoiminen. Peilaamme tämän jälkeen tutkimusten antia ja performatiivisuuden tutkimusohjelmaan sisältyviä ohjeistuksia omaan tapaustutkimukseemme, jonka kohteena on Sitran pyrkimys kotouttaa vaikuttavuusinvestoiminen Suomeen. Osoitamme tarkastelumme pohjalta, että keskittyminen taloustieteen performatiivisuuteen jättää muut vaikuttavuusinvestoimisessa keskeiset performatiivisuuden muodot katveeseen. Luonnostelemme tältä pohjalta moniperformatiivisuudeksi kutsumaamme tutkimustapaa. Ajatus tutkimuksellisesta moniperformatiivisuudesta vastaa Callonin ohjelman päivittämistarpeeseen havainnoimalla ilmiöitä eri arvottamisen muotojen, järkeilytyylien ja perustelumallien yhdistelminä.
Selittäminen vai interventio
Authors: Pulkkinen Tuija
Published: June 2021

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Ibadah Online dalam Perspektif Alkitab dan Relevansinya pada Masa serta Pasca Pandemi Covid-19
Authors: Sunarto Sunarto
Published: June 2021

Masalah utama dalam penulisan artikel ini adalah bolehkah gereja menyelenggarakan ibadah secara online? Pada awalnya ada yang tidak setuju, tetapi juga ada yang setuju. Jadi tujuan dari penulisan artikel ini ingin menguraikan dasar Alkitab yang menjadi acuan bagi penyelenggara ibadah secara online. Menjelaskan keunggulan dan kelemahan dari ibadah secara offline. Menjelaskan keunggulan dan kelemahan dari ibadah secara online. Menjelaskan relevansinya ibadah online pada masa dan pasca pandemi Covid-19. Di samping menguraikan hal-hal tersebut artikel ini sekaligus sebagai upaya pencerahan terhadap hakikat ibadah Kristen yang benar dalam memasuki era baru di masa pandemi dan perkembangan yang pesat dalam teknologi digital. Metode penelitian dalam penulisan artikel ini adalah analisis kepustakaan dengan metode deskriptif. Kesimpulannya adalah ibadah online di masa dan paska pandemi Covid-19 masih tetap relevan untuk tetap diselenggarakan.
15-year variability of desert dust optical depth on global and regional scales
Authors: Logothetis Stavros-Andreas , Salamalikis Vasileios , Gkikas Antonis , Kazadzis Stelios , Amiridis Vassilis , Kazantzidis Andreas
Published: June 2021

Abstract. This study aims to investigate the global, regional and seasonal temporal dust changes as well as the effect of dust particles on total aerosol loading, using the MIDAS fine resolution dataset. MIDAS delivers dust optical depth (DOD) at fine spatial resolution (0.1° × 0.1°) spanning from 2003 to 2017. Within this study period, the dust burden has been increased across Central Sahara (up to 0.023 yr−1) and Arabian Peninsula (up to 0.024 yr−1). Both regions observed their highest seasonal trends in summer (up to 0.031 yr−1). On the other side, declining DOD trends are encountered in Western (down to −0.015 yr−1) and Eastern (down to −0.023 yr−1) Sahara, Bodélé Depression (down to −0.021 yr−1), Thar (down to −0.017 yr−1) and Gobi (down to −0.011 yr−1) Deserts and Mediterranean Basin (down to −0.009 yr−1). At spring, the most negative seasonal trends are recorded in Bodélé Depression (down to −0.038 yr−1) and Gobi Desert (down to −0.023 yr−1) whereas in West (down to −0.028 yr−1) and East Sahara (down to −0.020 yr−1), and Thar Desert (down to −0.047 yr−1) at summer. Over western and eastern sector of Mediterranean Basin, the most negative seasonal trends are computed at summer (down to −0.010 yr−1) and spring (down to −0.006 yr−1), respectively. The effect of DOD to the total aerosol optical depth (AOD) changes is determined calculating the DOD to AOD ratio. Over Sahara Desert the median ratio values range from 0.83 to 0.95 whereas in other dust affected areas (Arabian Peninsula, South Mediterranean, Thar and Gobi Deserts) is recorded approximately around 0.6. In addition, a comprehensive analysis of the factors effecting the sign, the magnitude and the statistical significance of the calculated trends is conducted. Firstly, the implications between the implementation of geometric mean instead of arithmetic mean to trend calculations are discussed revealing that the arithmetic-based trends tend to overestimate compared with the geometric-based trends both over land and ocean. Secondly, an analysis interpreting the differences in trend calculations under different spatial resolutions (fine and coarse) and time intervals is conducted, which sounds a critical aspect when satellite-based measurements are utilized.
Comparison of influence between two types of cold surge on haze dispersion in Eastern China
Authors: Zhang Shiyue , Zeng Gang , Yang Xiaoye , Wu Ruixi , Yin Zhicong
Published: June 2021

Abstract. Cold surge (CS) is considered as a favorable weather process to improve air quality and is widely recognized. However, there is no detailed study on the differences in the dispersion ability of different types of CSs to haze days in eastern China (HDEC). This paper uses the hierarchical clustering algorithm to classify the cool season (November to February of the following year) CSs across eastern China into blocking and wave-train CSs and compares their influences on the number of HDEC from 1980 to 2017. Results show that the wave-train CS can significantly improve the visibility in eastern China and generally make the high air quality last for about 2 days longer than the blocking CS, which indicates that the blocking CS has a weaker ability to dissipate HDEC compared with the wave-train CS. The CSs affect the HDEC by changing these meteorological elements like thermal inversion potential, horizontal surface wind, sea level pressure (SLP), and surface air temperature (SAT). 4 days after the CSs outbreak, the variations of thermal inversion potential and horizontal surface wind of two types of CSs tend to be consistent. However, the negative SAT anomalies, and the positive SLP anomalies caused by the blocking CSs lasted shorter than those caused by the wave-train CSs, which forms favorable conditions for the rapid growth of HDEC. Furthermore, results show that in recent years, especially after the 1990s, the frequency of wave-train CSs has decreased significantly, while the frequency of blocking CSs has slightly increased, indicating that the overall ability of CSs to dissipate HDEC has weakened in general.
Bias-correcting carbon fluxes derived from land-surface satellite data for retrospective and near-real-time assimilation systems
Authors: Weir Brad , Ott Lesley E. , Collatz George J. , Kawa Stephan R. , Poulter Benjamin , Chatterjee Abhishek , Oda Tomohiro , Pawson Steven
Published: June 2021

Abstract. The ability to monitor and understand natural and anthropogenic variability in
atmospheric carbon dioxide (CO2) is a growing need of many stakeholders across the world. Systems that assimilate satellite observations, given their
short latency and dense spatial coverage, into high-resolution global models are valuable, if not essential, tools for addressing this need. A notable drawback of modern assimilation systems is the long latency of many vital input datasets; for example, inventories, in situ measurements, and reprocessed remote-sensing data can trail the current date by months to years. This paper describes techniques for bias-correcting surface fluxes derived from satellite
observations of the Earth's surface to be consistent with constraints from
inventories and in situ CO2 datasets. The techniques are applicable in both short-term forecasts and retrospective simulations, thus taking advantage of the coverage and short latency of satellite data while reproducing the major features of long-term inventory and in situ records. Our approach begins with
a standard collection of diagnostic fluxes which incorporate a variety of
remote-sensing driver data, viz. vegetation indices, fire radiative power, and nighttime lights. We then apply an empirical sink so that global budgets of the diagnostic fluxes match given atmospheric and oceanic growth rates for each year. This step removes coherent, systematic flux errors that produce biases in CO2 which mask the signals an assimilation system hopes to capture. Depending on the simulation mode, the empirical sink uses different choices of atmospheric growth rates: estimates based on observations in retrospective mode
and projections based on seasonal forecasts of sea surface temperature in
forecasting mode. The retrospective fluxes, when used in simulations with
NASA's Goddard Earth Observing System (GEOS), reproduce marine boundary layer
measurements with comparable skill to those using fluxes from a modern
inversion system. The forecasted fluxes show promising accuracy in their
application to the analysis of changes in the carbon cycle as they occur.
Identifying meteorological influences on marine low-cloud mesoscale morphology using satellite classifications
Authors: Mohrmann Johannes , Wood Robert , Yuan Tianle , Song Hua , Eastman Ryan , Oreopoulos Lazaros
Published: June 2021

Abstract. Marine low-cloud mesoscale morphology in the southeastern Pacific Ocean is analyzed using a large dataset of classifications spanning 3 years generated by machine learning methods. Meteorological variables and cloud properties are composited by the mesoscale cloud type of the classification, showing distinct meteorological regimes of marine low-cloud organization from the tropics to the midlatitudes. The presentation of
mesoscale cellular convection, with respect to geographic distribution,
boundary layer structure, and large-scale environmental conditions, agrees
with prior knowledge. Two tropical and subtropical cumuliform boundary layer regimes, suppressed cumulus and clustered cumulus, are studied in detail. The patterns in precipitation, circulation, column water vapor, and cloudiness are consistent with the representation of marine shallow
mesoscale convective self-aggregation by large eddy simulations of the
boundary layer. Although they occur under similar large-scale conditions,
the suppressed and clustered low-cloud types are found to be well separated
by variables associated with low-level mesoscale circulation, with surface
wind divergence being the clearest discriminator between them, regardless of whether reanalysis or satellite observations are used. Clustered regimes are associated with surface convergence, while suppressed regimes are associated with surface divergence.
A method for liquid spectrophotometric measurement of total and water-soluble iron and copper in ambient aerosols
Authors: Yang Yuhan , Gao Dong , Weber Rodney J.
Published: June 2021

Abstract. Determination of transition metals in ambient aerosols is important due to their toxicity to human health. However, the traditional measurement techniques for metal analysis are often costly and require sophisticated instruments. In this study, we developed and verified relatively low-cost liquid spectrophotometric methods for the measurements of iron (Fe) and copper (Cu), the two most abundant transition metals in ambient fine particulate matter (PM2.5). For Fe analysis, we utilized a ferrozine-based colorimetric method, which has been frequently used for water-soluble (WS) Fe determination, and further extended this approach for the measurement of total Fe (water-soluble + water-insoluble). In this
method, Fe is quantified through the formation of a light-absorbing
ferrozine–Fe(II) complex (absorbance at 562 nm). A similar colorimetric
method, which forms a bathocuproine–Cu(I) complex absorbing light at 484 nm, was developed and examined for measurement of WS and total Cu. These methods were applied to 24 h integrated filter samples collected in
urban Atlanta. Based on PM2.5 ambient aerosols, total and water-soluble
Fe and Cu concentrations were in good agreement with inductively coupled
plasma mass spectrometry (ICP-MS) measurements (slopes 1.0±0.1,
r2>0.89). The water-soluble components, operationally defined as those species in the aqueous filter extract that pass through a
0.45 µm filter, were further characterized by ultrafiltration, which showed that roughly 85 % of both the Fe and Cu in the water-soluble fraction was composed of species smaller than nominally 4 nm.
Sensitivity of Aeolus HLOS winds to temperature and pressure specification in the L2B processor
Authors: Šavli Matic , Pourret Vivien , Payan Christophe , Mahfouf Jean-François
Published: June 2021

Abstract. The retrieval of wind from the first Doppler wind lidar of European Space Agency (ESA) launched in space in August 2018 is based on a series of corrections necessary to provide observations of a quality useful for numerical weather prediction (NWP). In this paper we examine the properties of the Rayleigh–Brillouin correction necessary for the retrieval of horizontal line-of-sight wind (HLOS) from a Fabry–Pérot interferometer. This correction is taking into account the atmospheric stratification, namely temperature and pressure information that are provided by a NWP model as suggested prior to launch. The main goal of the study is to evaluate the impact of errors in simulated atmospheric temperature and pressure information on the HLOS sensitivity by comparing the Integrated Forecast System (IFS) and Action de Recherche Petite Echelle Grande Echelle (ARPEGE) global model temperature and pressure short-term forecasts collocated with the Aeolus orbit. These errors are currently not taken into account in the computation of the HLOS error estimate since its contribution is believed to be small. This study largely confirms this statement to be a valid assumption, although it also shows that model errors could locally (i.e. jet-stream regions, below 700 hPa over both earth poles and in stratosphere) be significant. For future Aeolus follow-on missions this study suggests considering realistic estimations of errors in the HLOS retrieval algorithms, since this will lead to an improved estimation of the Rayleigh–Brillouin sensitivity uncertainty contributing to the HLOS error estimate and better exploitation of space lidar winds in NWP systems.
Magnetotail Reconnection Asymmetries in a Small, Earth-Like Magnetosphere
Authors: Bard Christopher , Dorelli John
Published: June 2021

Abstract. We use a newly developed global Hall MHD code to investigate how reconnection drives magnetotail asymmetries in small magnetospheres. Here, we consider a scaled-down, Earth-like magnetosphere where the ion inertial length (δi) is artificially inflated to one planetary radius (the real Earth's δi ≈ 1/15–1/20 RE in the magnetotail). This results in a magnetotail width on the order of 30 δi, slightly smaller than Mercury's tail and much smaller than Earth's. At this small size, we find that the Hall effect has significant impact on the global flow pattern, changing from a symmetric, Dungey-like convection under resistive MHD to an asymmetric pattern similar to that found in previous Hall MHD simulations of Ganymede's subsonic magnetosphere as well as other simulations of Mercury's using multi-fluid or embedded kinetic physics. We demonstrate that the Hall effect is sufficient to induce a dawnward asymmetry in observed dipolarization front locations and find quasi-periodic global scale dipolarizations under steady, southward solar wind conditions. On average, we find a thinner current sheet dawnward; however, the measured thickness oscillates with the dipolarization cycle. During the flux-pileup stage, the dawnward current sheet can be thicker than the duskward sheet. This could be an explanation for recent observations that suggest Mercury's current sheet is actually thicker on the duskside: a sampling bias due to a longer-lasting "thick" state in the sheet.
Experimental production of charcoal morphologies to discriminate fuel source and fire type: an example from Siberian taiga
Authors: Feurdean Angelica
Published: June 2021

Abstract. The analysis of charcoal fragments in peat and lake sediments is the most
widely used approach to reconstruct past biomass burning. With a few
exceptions, this method typically relies on the quantification of the total
charcoal content of the sediment. To enhance charcoal analyses for the
reconstruction of past fire regimes and make the method more relevant to
studies of both plant evolution and fire management, the extraction of more
information from charcoal particles is critical. Here, I used a muffle oven
to burn seven fuel types comprising 17 species from boreal Siberia (near
Teguldet village), which are also commonly found in the Northern Hemisphere,
and built on published schemes to develop morphometric and finer diagnostic
classifications of the experimentally charred particles. I then combined
these results with those from fossil charcoal from a peat core taken from
the same location (Ulukh-Chayakh mire) in order to demonstrate the relevance of
these experiments to the fossil charcoal records. Results show that
graminoids, Sphagnum, and wood (trunk) lose the most mass at low burn temperatures
(<300 ∘C), whereas heathland shrub leaves, brown moss,
and ferns lose the most mass at high burn temperatures. This suggests that species with low
mass retention in high-temperature fires are likely to be under-represented
in the fossil charcoal record. The charcoal particle aspect ratio appeared
to be the strongest indicator of the fuel type burnt. Graminoid charcoal
particles are the most elongate (6.7–11.5), with a threshold above 6 that may be
indicative of wetland graminoids; leaves are the shortest and bulkiest
(2.1–3.5); and twigs and wood are intermediate (2.0–5.2). Further, the use
of fine diagnostic features was more successful in separating wood,
graminoids, and leaves, but it was difficult to further differentiate these
fuel types due to overlapping features. High-aspect-ratio particles,
dominated by graminoid and Sphagnum morphologies, may be robust indicators of low-temperature surface fires, whereas abundant wood and leaf morphologies as well as
low-aspect-ratio particles are indicative of higher-temperature fires.
However, the overlapping morphologies of leaves and wood from trees and
shrubs make it hard to distinguish between high-intensity surface fires,
combusting living shrubs and dead wood and leaves, and high-intensity crown
fires that have burnt living trees. Distinct particle shape may also
influence charcoal transportation, with elongated particles (graminoids)
potentially having a more heterogeneous distribution and being deposited
farther away from the origin of fire than the rounder, polygonal leaf
particles. Despite these limitations, the combined use of charred-particle
aspect ratios and fuel morphotypes can aid in the more robust interpretation of
fuel source and fire-type changes. Lastly, I highlight the further
investigations needed to refine the histories of past wildfires.
Ten years of temperature and wind observation on a 45-m tower at Dome C, East Antarctic plateau
Authors: Genthon Christophe , Veron Dana E. , Vignon Etienne , Six Delphine , Dufresne Jean-Louis , Madeleine Jean-Baptiste , Sultan Emmanuelle , Forget François
Published: June 2021

Abstract. Long-term, continuous in situ observations of the near-surface atmospheric boundary layer are critical for many weather and climate applications. Although there is a proliferation of surface stations globally, especially in and around populous areas, there are notably fewer tall meteorological towers with multiple instrumented levels. This is particularly true in remote and extreme environments such as the Eastern Antarctic plateau. In the article, we present and analyze 10 years of data from 6 levels of meteorological instrumentation mounted on a 42-m tower located at Dome C, East Antarctica near the Concordia research station, producing a unique climatology of the near-surface atmospheric environment (Genthon et al., 2021,a,b). Monthly temperature and wind data demonstrate the large seasonal differences in the near-surface boundary layer dynamics, depending on the presence or absence of solar surface forcing. Strong vertical temperature gradients (inversions) frequently develop in calm, winter conditions, while vertical convective mixing occurs in the summer leading to near-uniform temperatures along the tower. Seasonal variation in wind speed is much less notable at this location than the temperature variation as the winds are less influenced by the solar cycle; there are no katabatic winds as Dome C is quite flat. Harmonic analysis confirms that most of the energy in the power spectrum is at diurnal, annual and semi-annual time scales. Analysis of observational uncertainty and comparison to reanalysis data from ERA-5 indicate that wind speed is particularly difficult to measure at this location. Data are distributed on PANGAEA data repository, see data availability section.
Generation of autogenic knickpoints in laboratory landscape experiments evolving under constant forcing
Authors: de Lavaissière Léopold , Bonnet Stéphane , Guyez Anne , Davy Philippe
Published: June 2021

Abstract. The upward propagation of knickpoints in the long profiles of rivers is commonly related to discrete changes in tectonics, climate or base-level. However, the recognition that some knickpoints may form autogenically, independently of any external perturbation, may challenge these interpretations. We investigate here the genesis and dynamics of such autogenic knickpoints in laboratory experiments at the drainage basin scale, where landscape evolved in response to constant rates of base-level fall and precipitation. Despite these constant forcing, we observe that knickpoints regularly initiate in rivers at the catchments’ outlets throughout experiments duration. Their propagation rate does not decrease monotonically in relationship with the decrease in drainage area as predicted by stream-power based models, but first increases with a peak retreat rate in the mid-part of catchments. Their initiation coincides with rivers narrowing and increasing their shear stress. Then, rivers widening leads to a decrease in shear stress and incision rate below the base-level fall rate once knickpoints have propagated upward, creating an unstable situation that ends up with the formation of a new knickpoint. We propose a new model of cyclic generation of autogenic knickpoints controlled by river width dynamics. It illustrates the need to consider autogenic processes in the generation of knickpoints and for deciphering variation of tectonic and climatic processes from landscape records.
Virtual strike and dip – Advancing inclusive and accessible field geology
Authors: Bursztyn Natalie , Sajjadi Pejman , Riegel Hannah , Huang Jiawei , Wallgrün Jan Oliver , Zhao Jiayan , Masters Bart , Klippel Alexander
Published: June 2021

Abstract. Accessibility and inclusivity in field geology have become increasingly important issues to address in geoscience education and have long been set aside due to the tradition of field geology and the laborious task of making it inclusive to all. Although a popular saying among geologists is “the best geologists see the most rocks”, field trips cost money, time, and are only accessible for those who are physically able to stay outside long hours. With the availability of 3D block diagrams, an onslaught of virtual learning environments is becoming increasingly viable. Strike and dip is at the core of any field geologist’s education and career; learning and practicing these skills is fundamental to making geologic maps and understanding the regional geology of an area. In this paper, we present the Strike and Dip virtual tool (SaD) with the objective of teaching the principles of strike and dip for geologic mapping to introductory geology students. We embedded the SaD tool into an introductory geology course and recruited 147 students to participate in the study. Participants completed two maps using the SaD tool and reported on their experiences through a questionnaire. The SaD tool was overall perceived positively by students. Furthermore, some individual differences among students proved to be important contributing factors to their experiences and subjective assessments of learning. When controlling for participants’ past experience with similar software, our results indicate that students highly familiar with navigating geographical software perceived the virtual environment of the tool to be significantly more realistic and easier to use compared to those with lower levels of familiarity. Our results are corroborated by a qualitative assessment of participants’ feedback to two open-ended questions, highlighting both the overall effectiveness of the SaD tool, and the effect of geographical software familiarity on measures of experience and learning.
Constraining stochastic 3-D structural geological models with topology information using approximate Bayesian computation in GemPy 2.1
Authors: Schaaf Alexander , de la Varga Miguel , Wellmann Florian , Bond Clare E.
Published: June 2021

Abstract. Structural geomodeling is a key technology for the visualization and
quantification of subsurface systems. Given the limited data and the resulting
necessity for geological interpretation to construct these geomodels,
uncertainty is pervasive and traditionally unquantified. Probabilistic
geomodeling allows for the simulation of uncertainties by automatically
constructing geomodel ensembles from perturbed input data sampled from
probability distributions. But random sampling of input parameters can lead to
construction of geomodels that are unrealistic, either due to modeling artifacts
or by not matching known information about the regional geology of the modeled
system. We present a method to incorporate geological information in the
form of known geomodel topology into stochastic simulations to constrain
resulting probabilistic geomodel ensembles using the open-source geomodeling
software GemPy. Simulated geomodel realizations are checked against topology
information using an approximate Bayesian computation approach to avoid the
specification of a likelihood function. We demonstrate how we can infer the
posterior distributions of the model parameters using topology information in two
experiments: (1) a synthetic geomodel using a rejection sampling scheme
(ABC-REJ) to demonstrate the approach and (2) a geomodel of a subset of the
Gullfaks field in the North Sea comparing both rejection sampling and a
sequential Monte Carlo sampler (ABC-SMC). Possible improvements to processing
speed of up to 10.1 times are discussed, focusing on the use of more advanced
sampling techniques to avoid the simulation of unfeasible geomodels in the first
place. Results demonstrate the feasibility of using topology graphs as a summary
statistic to restrict the generation of geomodel ensembles with known
geological information and to obtain improved ensembles of probable geomodels
which respect the known topology information and exhibit reduced uncertainty
using stochastic simulation methods.
How well are we able to close the water budget at the global scale?
Authors: Lehmann Fanny , Vishwakarma Bramha Dutt , Bamber Jonathan
Published: June 2021

Abstract. The water budget equation describes the exchange of water between the land, ocean and atmosphere. Being able to adequately close the water budget gives confidence in our ability to model and/or observe the spatiotemporal variations in the water cycle and its components. Due to advances in observation techniques, satellite sensors, and modelling, a number of data products are available that represent the components of water budget both in space and time. Despite these advances, closure of the water budget at global scale has been elusive. In this study, we attempt to close the global water budget using precipitation, evapotranspiration, and runoff data at the catchment scale. The large number of recent state-of-the-art datasets provides a new evaluation of well-used datasets. These estimates are compared to terrestrial water storage (TWS) changes as measured by the GRACE satellite mission. We investigated 189 river basins covering more than 90 % of the continental land area. TWS changes derived from the water balance equation were compared against GRACE data using two metrics: the Nash-Sutcliffe Efficiency (NSE) and cyclostationary NSE. These were used to assess the performance of more than 1600 combinations of the various datasets considered. We found a positive NSE and cyclostationary NSE in 99 % and 62 % of the basins examined, respectively. This means that TWS changes reconstructed from the water balance equation were more accurate than the long-term (NSE) and monthly (cyclostationary NSE) mean of GRACE time series in the corresponding basins. By analyzing different combinations of the datasets that make up the water balance, we identified data products that performed well in certain regions based on, for example, climatic zone. We identified that some of the good results were obtained due to cancellation of errors in poor estimates of water budget components. Therefore, we used coefficients of variation to determine the relative quality of a data product, which helped us to identify bad combinations giving us good results. In general, water budget components from the ERA5 Land and the Catchment Land Surface Model (CLSM) performed better than other products for most climatic zones. Conversely, the latest version of the Catchment Land Surface Model, v2.2, performed poorly for evapotranspiration in snow-dominated catchments compared, for example, to its predecessor and other datasets available. Thus, the nature of the catchment dynamics and balance between components affects the optimum combination of datasets. For regional studies, the combination of datasets that provides the most realistic TWS for a basin will depend on its climatic conditions and factors that cannot be determined a-priori. We believe, the results of this study provide a roadmap for studying the water budget at the catchment scale.
A CAPSNETS APPROACH TO PAVEMENT CRACK DETECTION USING MOBILE LASER SCANNNING POINT CLOUDS
Authors: Zhu W. , Tan W. , Ma L. , Zhang D. , Li J. , Chapman M. A.
Published: June 2021

Abstract. Routine pavement inspection is crucial to keep roads safe and reduce traffic accidents. However, traditional practices in pavement inspection are labour-intensive and time-consuming. Mobile laser scanning (MLS) has proven a rapid way for collecting a large number of highly dense point clouds covering roadway surfaces. Handling a huge amount of unstructured point clouds is still a very challenging task. In this paper, we propose an effective approach for pavement crack detection using MLS point clouds. Road surface points are first converted into intensity images to improve processing efficiency. Then, a Capsule Neural Network (CapsNet) is developed to classify the road points for pavement crack detection. Quantitative evaluation results showed that our method achieved the recall, precision, and F1-score of 95.3%, 81.1%, and 88.2% in the testing scene, respectively, which demonstrated the proposed CapsNet framework can accurately and robustly detect pavement cracks in complex urban road environments.
EVALUATING DIFFERENT WATER-LAND-BOUNDARY APPROXIMATIONS TO IMPROVE SAR-DERIVED DIGITAL ELEVATION MODELS
Authors: Schneider B. , Wortmeyer E. , Schmitz S. , Thiele A. , Havel P. , Dirks H.
Published: June 2021

Abstract. The coastline of the German Wadden Sea is constantly subjected to the tides and the tidal-induced environmental changes like erosion and accumulation of sediments need to be monitored constantly. This task requires digital elevation models (DEMs), which are derived from remote sensing data. To model those DEMs, a separation of data collected over landmasses and water bodies is required. In the GeoWAM project the potential of airborne SAR-data (F-SAR) is investigated for monitoring purposes in the Wadden Sea. As part of the project, this paper focuses on the suitability of F-SAR data regarding the derivation of water-land-boundaries (WLBs). Therefore, water-land-boundaries based on independent data sets are compared and evaluated. Analyzed data sets include data collected via F-SAR, airborne laserscanning (ALS), on site GNSS measured WLB points and sea-level data from two acoustic gauges. The algorithms were tested on a study site on Spiekeroog island. Our results show, that the accuracies of the derived WLBs mostly depend on the on-site topography and sediments. The spatial deviation between the reference data and the approximated WLBs is mostly less than 2 m horizontally and 0.15 m vertically. Identified challenges to overcome are mostly related to processing of F-SAR data in areas with highly water saturated sediments. Our results suggest, that F-SAR data in tidal flats is not necessarily dependent on further supplementing surveys, as one of the main advantages of the F-SAR data is the potential to derive DEMs and WLBs from the same data set.
PREFACE: TECHNICAL COMMISSION I
Authors: Hinz S. , Feitosa R. Q. , Weinmann M. , Jutzi B.
Published: June 2021

Abstract. For ISPRS Technical Commission I (TC I), 76 submissions for the 2021 Congress edition of ISPRS Annals and ISPRS Archives were received. This included both full paper and abstract submissions from all over the world. Continuing the success of double blind paper reviewing in preparation of the 2016 Prague congress, the 2018 Karlsruhe symposium as well as the 2020 edition of the ISPRS congress, also this time, TC I organized a strict peer-reviewing process. This included double-blind reviewing for full papers as well as a two-stage evaluation of abstract submissions – first stage based on the submitted abstracts (“conditional acceptance”), and second stage after submission of the respective final papers.For the 2021 edition of the ISPRS congress, we received 32 full paper submissions and 46 abstract submissions, which underlines the trend towards full paper submissions compared to previous TC I events.17 full papers passed the double-blind peer-review process and were accepted for publication in the ISPRS Annals (acceptance rate 53%); none of the papers was reviewed by less than two reviewers; for the majority of full papers, three or four reviews were obtained. Abstract submissions and their respective final papers were reviewed by a team of professionals. In total, 28 papers were accepted to the ISPRS Archives.Strict peer-reviewing relies on many voluntary reviewers spending their time for reading and evaluating the submissions. We would like to express our thanks to our reviewing team – especially since they were again willing to contribute to the review process just after completion of the 2020 edition of the ISPRS congress.The manuscripts in both the ISPRS Annals and Archives cover a broad range of topics related to remote sensing platforms, technologies, systems and related methods and reflect the current trends in algorithmic research and developments in sensing and data acquisition methods. Noteworthy is that numerous contributions were again submitted to Intercommission WGs of TC I with TC II and TC IV, which underlines the continuing trend towards an integral approach to sensors, systems and methods in photogrammetry, remote sensing and mobile mapping.
ROAD TYPE CLASSIFICATION OF MLS POINT CLOUDS USING DEEP LEARNING
Authors: Bai Q. , Lindenbergh R. C. , Vijverberg J. , Guelen J. A. P.
Published: June 2021

Abstract. Functional classification of the road is important to the construction of sustainable transport systems and proper design of facilities. Mobile laser scanning (MLS) point clouds provide accurate and dense 3D measurements of road scenes, while their massive data volume and lack of structure also bring difficulties in processing. 3D point cloud understanding through deep neural networks achieves breakthroughs since PointNet and arouses wide attention in recent years. In this paper, we study the automatic road type classification of MLS point clouds by employing a point-wise neural network, RandLA-Net, which is designed for consuming large-scale point clouds. An effective local feature aggregation (LFA) module in RandLA-Net preserves the local geometry in point clouds by formulating an enhanced geometric feature vector and learning different point weights in a local neighborhood. Based on this method, we also investigate possible feature combinations to calculate neighboring weights. We train on a colorized point cloud from the city of Hannover, Germany, and classify road points into 7 classes that reveal detailed functions, i.e., sidewalk, cycling path, rail track, parking area, motorway, green area, and island without traffic. Also, three feature combinations inside the LFA module are examined, including the geometric feature vector only, the geometric feature vector combined with additional features (e.g., color), and the geometric feature vector combined with local differences of additional features. We achieve the best overall accuracy (86.23%) and mean IoU (69.41%) by adopting the second and third combinations respectively, with additional features including Red, Green, Blue, and intensity. The evaluation results demonstrate the effectiveness of our method, but we also observe that different road types benefit the most from different feature settings.