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See detailElfriede Jelinek : l'abîme sous nos pieds
Neelsen, Sarah ULiege

Article for general public (2017)

Entretien avec Christian Longchamp sur l’œuvre d'Elfriede Jelinek à l'occasion de la première de l'opéra contemporain "Kein Licht" (mise en scène Nicolas Stehmann , musique Philippe Manoury) à l'Opéra ... [more ▼]

Entretien avec Christian Longchamp sur l’œuvre d'Elfriede Jelinek à l'occasion de la première de l'opéra contemporain "Kein Licht" (mise en scène Nicolas Stehmann , musique Philippe Manoury) à l'Opéra national du Rhin. [less ▲]

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See detailChemical abundances of fast-rotating massive stars. I. Description of the methods and individual results
Cazorla, Constantin ULiege; Morel, Thierry ULiege; Nazé, Yaël ULiege et al

in Astronomy and Astrophysics (2017), 603(A56),

Aims: Recent observations have challenged our understanding of rotational mixing in massive stars by revealing a population of fast- rotating objects with apparently normal surface nitrogen abundances ... [more ▼]

Aims: Recent observations have challenged our understanding of rotational mixing in massive stars by revealing a population of fast- rotating objects with apparently normal surface nitrogen abundances. However, several questions have arisen because of a number of issues, which have rendered a reinvestigation necessary; these issues include the presence of numerous upper limits for the nitrogen abundance, unknown multiplicity status, and a mix of stars with different physical properties, such as their mass and evolutionary state, which are known to control the amount of rotational mixing. Methods: We have carefully selected a large sample of bright, fast-rotating early-type stars of our Galaxy (40 objects with spectral types between B0.5 and O4). Their high-quality, high-resolution optical spectra were then analysed with the stellar atmosphere modelling codes DETAIL/SURFACE or CMFGEN, depending on the temperature of the target. Several internal and external checks were performed to validate our methods; notably, we compared our results with literature data for some well-known objects, studied the effect of gravity darkening, or confronted the results provided by the two codes for stars amenable to both analyses. Furthermore, we studied the radial velocities of the stars to assess their binarity. Results: This first part of our study presents our methods and provides the derived stellar parameters, He, CNO abundances, and the multiplicity status of every star of the sample. It is the first time that He and CNO abundances of such a large number of Galactic massive fast rotators are determined in a homogeneous way. [less ▲]

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See detailPractical Trajectories of Parametric Tools in Small and Medium Architectural Firms
Stals, Adeline ULiege; Elsen, Catherine ULiege; Jancart, Sylvie ULiege

in Future trajectories for computation in design (2017, July)

Initially used as an extension of hand-drawing tools, digital design tools and moreover parametric ones are nowadays deeply modifying the architectural design process. Big offices with star-architects ... [more ▼]

Initially used as an extension of hand-drawing tools, digital design tools and moreover parametric ones are nowadays deeply modifying the architectural design process. Big offices with star-architects were able to adopt these tools but most architects working in a small office are still trying to cope with these parametric design tools. Several questions arise in this regard: what digital tools do architects usually use? Do they express interest for new technologies and software such as parametric ones? What is their understanding of the term “parametric architecture”? Why is this kind of tools still not largely adopted? Going through the results of an online survey, this paper first discusses the meaning of parametric design for architects. The contribution then analyzes the Belgian case regrouping mostly small and medium offices. It reflects particularly on the way architects do or do not implement these new digital tools in their workflows, and it sheds light on the fact that parametric tools also have the potential to free the creativity of SME’s. [less ▲]

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See detailOptimisation of Ship and Offshore Structures and Effective Waterway Infrastructures to Support the Global Economic Growth of a Country/Region
Rigo, Philippe ULiege; Bayatfar, Abbas ULiege; Buldgen, Loïc ULiege et al

in Ship Science & Technology (2017), 11

This paper is the written support of Prof. Ph. Rigo for his keynote lecture at the 5th International Congress for Ship Design and Naval Engineering (March 2017, Columbia). After presenting of the main ... [more ▼]

This paper is the written support of Prof. Ph. Rigo for his keynote lecture at the 5th International Congress for Ship Design and Naval Engineering (March 2017, Columbia). After presenting of the main research activities at ANAST, ULG, he discussed the way to improve the effectiveness of waterway infrastructures to support the global economic growth of a country/region. This paper includes the following parts:  Ship Structure Optimization: methodology to perform ship scantling optimization, decreasing steel weight and keeping the production cost at an acceptable level. We first review the links between “Design” and “Optimization” and secondly define the place of “Ship Structure Optimization” within the general framework of a “Ship Optimization”.  Ship impacts (Collision), with applications to navigation lock and dry dock gates: these gates have to be designed taking into account accidental loads, such as ship collisions. A new simplified analytical method is proposed, based on the so-called super-element method. This method was developed to rapidly assess the crashworthiness of the collided structure and avoid high computational effort of numerical simulations.  Inland waterway Navigation and the development in South America of Inland Waterway Classifications.  EMSHIP, European ERASMUS MUNDUS education program (www.emship.eu): the unique master in Ship & Offshore Structures awarded by the prestigious European Erasmus Mundus Program. Indeed, EMSHIP shares the outstanding experiences of educators, trainers, industrial partners and students in the rapidly developing areas of marine and offshore engineering industry. [less ▲]

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See detailGenetic evaluation of lactation persistency and total milk yield in dairy goats
Siqueira, O. H. G. B. D.; REIS MOTA, Rodrigo ULiege; Oliveira, H. R. et al

in Livestock Research for Rural Development (2017), 29(7),

Lactation persistency (LP) has been neglected over time in genetic evaluations of dairy goats. The main reason for this is the difficulty to infer about the lactation curve shape. However, some lactations ... [more ▼]

Lactation persistency (LP) has been neglected over time in genetic evaluations of dairy goats. The main reason for this is the difficulty to infer about the lactation curve shape. However, some lactations models such as Wood seem to be appropriate to provide persistency estimates under biological viewpoints. The aim of this study was to fit the Wood lactation model as well as to calculate and evaluate LP as selection criteria in dairy goat breeding programs through genetic parameters estimates. A total of 23,265 first lactation test day milk yield observations from 900 animals were used. The Wood random regression model was primarily fitted to estimate the lactation curve parameters (a, b and c), and then LP and total milk yield (TMY). Posteriorly, a multi-trait animal model was fitted considering simultaneously LP and TMY. The heritability estimates were 0.31 and 0.04 for TMY and LP, respectively. Based on the low LP heritability, selection based only on this trait might be inefficient. In conclusion, the results of this study suggests that selecting for high milk yields might result in high persistency since the genetic correlation between LP and TMY was moderate (0.39). [less ▲]

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See detailLe système semencier en question
Hecquet, Corentin ULiege; Stassart, Pierre M ULiege

in MILLE LIEUX (2017), 06

Les enjeux de biodiversité, le procès contre l’association Kokopelli, une demande accrue d’une alimentation saine et respectueuse, le désir d’autonomie d’agricul- teurs nourrissent les interrogations ... [more ▼]

Les enjeux de biodiversité, le procès contre l’association Kokopelli, une demande accrue d’une alimentation saine et respectueuse, le désir d’autonomie d’agricul- teurs nourrissent les interrogations par rapport au fonctionnement du système se- mencier. Cet article dépeint le système semencier européen et les critiques dont il fait l’objet. Ne sont pas abordés ici la réglementation phytosanitaire1, la certification de certaines espèces ni les OGM2. La législation européenne concernant la circula- tion des semences est régie par une dizaine de directives. Les droits de propriétés intellectuelles sur les semences sont régis, quant à eux, par les conventions au sein de l’Union internationale pour la Protection des Obtentions Végétales (UPOV) et au niveau européen, l’Office Communautaire des Variétés Végétales (OCVV) soutient les mécanismes de Certification d’Obtentions Végétales (COV). [less ▲]

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See detailPlanet remnants around evolved stars with CHEOPS
Van Grootel, Valérie ULiege

Conference (2017, July)

I will talk about the opportunity to study planets/asteroids/debris discs around evolved stars with CHEOPS. Compact, post-red giant stars (subdwarf B stars and white dwarfs) will be part of the core ... [more ▼]

I will talk about the opportunity to study planets/asteroids/debris discs around evolved stars with CHEOPS. Compact, post-red giant stars (subdwarf B stars and white dwarfs) will be part of the core program of TESS, which will provide, for the very first time, a census on the presence of planets/asteroids/debris discs around these stars. This will provide invaluable insights for the evolution of planetary systems and survival of close planets after the red giant phase. I will show how CHEOPS, with its larger collecting area and better sensitivity in the blue, could bring key added value to TESS for studying planets/asteroids/debris discs around evolved stars. [less ▲]

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See detailNew observations and asteroseismic analysis of the subdwarf B pulsator PG 1219+534
Van Grootel, Valérie ULiege; Péters, Marie-Julie; Green, Elizabeth M. et al

Conference (2017, July)

We present a new asteroseismic modeling of the hot B subdwarf (sdB) pulsator PG 1219+534, based on a 3-month campaign with the Mont4K/Kuiper combination at Mt Bigelow (Arizona) and on updated atmospheric ... [more ▼]

We present a new asteroseismic modeling of the hot B subdwarf (sdB) pulsator PG 1219+534, based on a 3-month campaign with the Mont4K/Kuiper combination at Mt Bigelow (Arizona) and on updated atmospheric parameters from high S/N low and medium resolution spectroscopy. On the basis of the nine independent pulsation periods extracted from the photometric light curve, we carried out an astroseismic analysis by applying the forward modeling approach using our latest (third and fourth generation) sdB models. Atmospheric parameters (Teff = 34 258±170 K, log g = 5.838±0.030) were used as independent constraints, as well as partial mode identification based on observed multiplet structures we ascribed to stellar rotation. The optimal model found is remarkably consistent between various analyses with third and fourth generation of sdB models, and also with previously published analysis with second generation sdB models. It corresponds to a sdB with a canonical mass (0.46 ± 0.02 M⊙), rather thin H-He envelope (log q(envl)= −3.75 ± 0.12), and close to He-burning exhaustion (Xcore(C + O) = 0.86 ± 0.05). We also investigate the internal rotation of the star. We find that PG 1219+534 rotates very slowly (Prot=34.91 ± 0.84 days) and that solid-body rotation is reached at least down to ∼60% of the radius. [less ▲]

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See detailA Markov-switching Generalized additive model for compound Poisson processes, with applications to operational losses models
Hambuckers, julien ULiege

Conference (2017, July)

This paper is concerned with modeling the behavior of random sums over time. Such models are particularly useful to describe the dynamics of operational losses, and to correctly estimate tail-related risk ... [more ▼]

This paper is concerned with modeling the behavior of random sums over time. Such models are particularly useful to describe the dynamics of operational losses, and to correctly estimate tail-related risk indicators. However, time-varying dependence structures make it a difficult task. To tackle these issues, we formulate a new Markov- switching generalized additive compound process combining Poisson and generalized Pareto distributions. This flexible model takes into account two important features: on the one hand, we allow all parameters of the compound loss distribution to depend on economic covariates in a flexible way. On the other hand, we allow this depen- dence to vary over time, via a hidden state process. A simulation study indicates that, even in the case of a short time series, this model is easily and well estimated with a standard maximum likelihood procedure. Relying on this approach, we analyze a novel dataset of 819 losses resulting from frauds at the Italian bank UniCredit. We show that our model improves the estimation of the total loss distribution over time, compared to standard alternatives. In particular, this model provides estimations of the 99.9% quantile that are never exceeded by the historical total losses, a feature particularly desirable for banking regulators. [less ▲]

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See detailA Markov-switching Generalized additive model for compound Poisson processes, with applications to operational losses models
Hambuckers, julien ULiege

Conference (2017, July)

This paper is concerned with modeling the behavior of random sums over time. Such models are particularly useful to describe the dynamics of operational losses, and to correctly estimate tail-related risk ... [more ▼]

This paper is concerned with modeling the behavior of random sums over time. Such models are particularly useful to describe the dynamics of operational losses, and to correctly estimate tail-related risk indicators. However, time-varying dependence structures make it a dfficult task. To tackle these issues, we formulate a new Markov-switching generalized additive compound process combining Poisson and generalized Pareto distributions. This flexible model takes into account two important features: on the one hand, we allow all parameters of the compound loss distribution to depend on economic covariates in a flexible way. On the other hand, we allow this dependence to vary over time, via a hidden state process. A simulation study indicates that, even in the case of a short time series, this model is easily and well estimated with a standard maximum likelihood procedure. Relying on this approach, we analyze a novel dataset of 819 losses resulting from frauds at the Italian bank UniCredit. We show that our model improves the estimation of the total loss distribution over time, compared to standard alternatives. In particular, this model provides estimations of the 99.9% quantile that are never exceeded by the historical total losses, a feature particularly desirable for banking regulators. [less ▲]

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See detailIn Search for Marine Antarctic Cyanobacteria
Lara, Yannick ULiege; Stelmach Pessi, Igor ULiege; Durieu, Benoit ULiege et al

Poster (2017, July)

Cyanobacteria are among the most ancient prokaryotic phyla present on the planet. They are thought to be responsible of two major geological changes and evolutionary process, the Great Oxygenation Event ... [more ▼]

Cyanobacteria are among the most ancient prokaryotic phyla present on the planet. They are thought to be responsible of two major geological changes and evolutionary process, the Great Oxygenation Event and the Endosymbiosis, which supported modern Life. In Polar freshwater and terrestrial ecosystems, cyanobacteria often constitute the major carbon fixers and the base of the food web. They are present in a wide range of habitat from hypersaline lakes to cryoconites. Nevertheless, their presence between the Polar front and Antarctic coast remains enigmatic. For a long time, it has been accepted that they were not present in Antarctic waters (Wilkins et al., 2012). However, they were found in low abundances in two publications, which were investigated the water column (Wilmotte et al., 2002; Wilkins et al., 2013). There is still a lack of information regarding their presence and role in Antarctic coastal waters. In order to investigate the presence of cyanobacteria in Antarctic marine benthos, samples were collected by scuba diving during two expeditions (2015, 2016) in the Lion’s channel, (Terre Adélie, Antarctica). Samples were directly frozen, dried or fixed with formaldehyde. DNA was extracted from one frozen sample and two dried samples. Then, 16S rRNA V3-V4 region was amplified using cyanobacteria-specific primers. Amplicons were sequenced using MiSeq Illumina technology. In parallel, fixed and frozen samples were scrutinized by microscopy. We obtained 14 558 reads, which were related to Cyanobacteria. They clustered into 97 OTUs and belong to six orders (Chroococcales, Nostocales, Oscillatoriales, Pseudanabaenales, Stigonematales, Synechococcales) with a large dominance of Pseudanabaenales. Thirty-one of the cyanobacterial OTUs were 100% identical to sequences of strains isolated from freshwater environment, and air samples from both temperate and Polar regions. Microscope observations revealed the presence of at least 3 cyanobacterial morphotypes including thin filaments, large Oscillatoriales, and a potential symbiotic or opportunist Nostocales. Albeit the low abundance of reads attributed to cyanobacteria, it remains necessary to assess their ecological role in Antarctic coastal waters. [less ▲]

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See detailAgency and delinquency among adolescence during their transition to adulthood: what role in the desistance process?
Puglia, Rosa ULiege; Glowacz, Fabienne ULiege

Poster (2017, June 31)

Recent studies have shown that agency plays an important role in the desistance process. This variable allows the transition from delinquent identity to non-delinquent identity. However, despite ... [more ▼]

Recent studies have shown that agency plays an important role in the desistance process. This variable allows the transition from delinquent identity to non-delinquent identity. However, despite increasing literature about this topic, there is a lack of consensus regarding the role of this variable in the desistance process. Also, the way to measure this phenomenon remains unclear. In our study, agency is thought within a border framework, namely the understanding of all kind of behavior. According to the social cognitive theory, emotional and cognitive processes influence human behavior: emotions and thoughts that will define ways of acting and will motivate behavioral changes. Outcomes expectancies can be help or hinder for the concretization of behavioral change. We conducted a qualitative research among adolescents (aged 17-18) who are engaged in a delinquent trajectory. Our objective are to understand how these young in transition to adulthood leave delinquent lifestyle by evaluating to their life course and delinquent course. Each participant was interviewed with a semi-structured interview. To ensure that the interviews provided rich insights into participants’ reality, the interview was designed to elicit detailed information on relevant themes including identity, turning point, future and delinquency trajectory. Desistance was not explicitly questioned. All interviews were taperecorded and analyzed using IPA method (Smith, 2003). Mastery Scale (Pearlin, 1978), Causal Attribution Scale (Rossier, 2002), Hope Scale (Snyder, 1991) and University Rhode Island Change Assessment Scale (McConnaughy, 1983) were also administered. We see that the younths interviewed are at different stage in their desistance process. All of them, persistent or desistant, consider taking a hold on their lives. These results encourage thinking agency in the understanding of all kind of behavior. We should then take into account the beliefs and expectations of results as a variable mediating the relationship between agency and desistance. [less ▲]

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See detailPopular Music Studies in French Universities
Pirenne, Christophe ULiege

Conference (2017, June 30)

Since the turn of the century, the study of popular music has become one of the hottest topics in French Universities. Of the 71 existing institutions, nearly all of them have one or another official ... [more ▼]

Since the turn of the century, the study of popular music has become one of the hottest topics in French Universities. Of the 71 existing institutions, nearly all of them have one or another official expert on that question. But between the study of a national or an international heritage, between scientific disciplines and humanities, researches devoted to popular music seems to be as perennial as fragmented. My paper will aim to present the evolution of recruitment in this area. Which disciplines were the most active in those recruitments and, beyond these raw numbers, what does it mean ? Why is the French academic situation so different to that of Italy for example ? What are the challenges of this academisation ? Which topics are taught under this heading ? I’d like to show that next to the objective reasons of this disciplinary interest, there are also various institutional issues that seems to correspond exactly to the assumptions of Bruno Latour (La science en action, 1989) and Edward Slowik (Structure of Musical Revolutions, 2007). [less ▲]

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See detailThe role of Gender, Race, and Class in Transnational Political Movements: Mexican and Colombian Women Engaging in Homeland Politics from Europe’s Capital
Lara-Guerrero, Larisa; Vivas Romero, Maria ULiege

Conference (2017, June 30)

Drug trafficking is a mounting security problem in Latin America, specifically for the primary producers of narcotics in the region: Mexico and Colombia. The security concern from both countries has ... [more ▼]

Drug trafficking is a mounting security problem in Latin America, specifically for the primary producers of narcotics in the region: Mexico and Colombia. The security concern from both countries has triggered the political and social mobilization of Mexican and Colombian migrants from abroad many of them from the Global City of Brussels. This paper unpacks the motivations and dynamics behind transnational political activism organized by Mexican and Colombian women living in Brussels. By integrating and revising insights from social movements theories, political transnationalism from migration studies and intersectionality studies, this paper elaborates on the role of migrant women organizing and sustaining transnational political movements to change the political conditions of their countries of origin. The ethnographic evidence presented in this paper reveals the importance to recognize the individual level in the analysis of transnational movements. Women are cognitive actors with political ideals and emotions whose political activism is highly influenced by social categorizations such as gender, race, class, and generation. [less ▲]

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See detailTable ronde : La formation continue chez les psychologues spécialisés en gérontologie : Pourquoi, pour quoi, par qui, quand et comment ?
Grotz, Catherine ULiege; Lagarde, Alexia; Stoykova, Ralitsa et al

Scientific conference (2017, June 30)

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See detailCaractérisation des argiles utilisées dans le secteur de la terre cuite de la région de Marrakech en vue d'améliorer la qualité des produits
El Boudour El Idrissi, Hicham ULiege

Doctoral thesis (2017)

The purpose of this study is to characterize the clay raw materials being exploited and used in the earthenware sector (pottery and building materials) of Marrakech region. It aims to improve product ... [more ▼]

The purpose of this study is to characterize the clay raw materials being exploited and used in the earthenware sector (pottery and building materials) of Marrakech region. It aims to improve product quality in 12 sites within a radius of 10 to 80 km around the city of Marrakech, where are active more than 850 potters spread over about 550 workshops. This characterization also aims at establishing a database on the properties of the raw materials of Marrakech and on the characteristics of the products. This will help in the selection of the most suitable materials, which generate the least defects, in restoring the historical sites of the city and in linking archaeological ceramics with their possible source of clayey material. A total of 34 samples of clay raw materials were collected from the various studied sites. 26 ceramic pastes were formed from these raw materials. Ceramic pastes have been characterized for their particle size (semi-wet sieving and laser particles size), chemical (XRF) and mineralogical compositions (XRD), plasticities (Atterberg limits), carbonate content (Bernard's calcimetry), drying behaviour (Bigot curve) and loss on ignition. The fired products were characterized by firing shrinkage, water porosity, compressive and flexural strengths and by SEM combined with EDX. The studied ceramic pastes show a large particle size variation: clay (18-66%), silt (12-53%) and sand (5-65%). Mineralogically, they are composed mainly of clay minerals (25-60%), quartz (20-55%), feldspars (5-35%), carbonates (≤15%), diopside (5-10%) and hematite (1-3%). Clay minerals are formed by illite (10-40%), kaolinite (5-15%), interstratified (≤10%), talc and pyrophyllite (≤10%), vermiculite (5%) and chlorite (≤5%). The chemical composition shows that the majority of the pastes are composed of SiO2 (48-74%), Al2O3 (12-20%), Fe2O3 (3-8%), CaO (0.4-8%), K2O (2-5%), MgO (0.5-3.5%), Na2O (0.1-2%), TiO2 (0.8-1.2%), P2O5 (≤ 0.4%) and MnO (≤ 3%). Plasticity varies from one paste to another with plasticity indices between 15 and 32. The shrinkage on drying is between 4 and 10%. For a firing temperature of 1050°C, the firing shrinkage of the various pastes is between 0.5 and 5%. The mineral transformations during firing are very diversified from one sample to another and from one site to another. The comparison of the obtained results shows that granulometry, mineralogy and degree of diagenesis are the main factors controlling plasticity. We showed a relationship between the properties of the pastes (particle size, mineralogy and plasticity) and the type of product. We proposed solutions for each of the many observed defects (poor quality of raw material, lime blowing, lime efflorescence, inadequate drying procedure, cracking, blisters, black hearts, crazing and poor ovens quality). In addition, this study valuated the clay raw materials of the Marrakech region for the use in the field of production of building materials. [less ▲]

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See detailAntarctic cyanobacteria: from diversity to genomics
Wilmotte, Annick ULiege

Conference (2017, June 30)

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See detailSoil Acidification in Southern China: Spatio-temporal Evolution and Effects on Phosphorus Availability
Zhou, Xiaoyang ULiege

Doctoral thesis (2017)

Rapid industrial development and intensive agriculture induced serious soil degradation in recent decades worldwide and specifically in China. In cropland, soil acidification and nutrient deficiency are ... [more ▼]

Rapid industrial development and intensive agriculture induced serious soil degradation in recent decades worldwide and specifically in China. In cropland, soil acidification and nutrient deficiency are often associated with increased use of nitrogen (N) fertilizers. Soil acidification can lead to reduction of phosphorus (P) availability, even though with high inputs of P fertilizer. The studies presented in the thesis deal with spatio-temporal evolution of soil pH in different soil types and land uses in southern China and effects of soil acidification on soil P availability. Evolution of inorganic P fractions in Red Soil was characterized upon fertilization trials, as a response to long-term fertilization and soil acidity changes. The first focus of the thesis deals with spatio-temporal evolution and main factors of soil acidification in different soil types, parent materials and land uses of Southern China. Firstly, data from 20 monitoring sites under 25-year fertilization on Paddy Soil were investigated to research changes of pH. Paddy Soil pH significantly declined from 1988-1998, then stabilized from 1998-2013 with conventional fertilization. Chemical N fertilization, manure application, soil available N and total N increases were significantly correlated with soil pH. Secondly, changes of pH in Red Soil and Paddy Soil were assessed in 32 monitoring sites of Hunan Province (Southern China) under 10-year fertilization in order to analyze soil acidification in different soil types and agro-systems. Soil pH decline was observed in Paddy Soils under rice-vegetable rotation but not observed in Paddy Soil under continuous cropping with rice. Soil pH significantly declined in Red Soil with high initial soil pH. Thirdly, spatio-temporal characteristics of soil pH were investigated by comparison of soil pH between 1982 and 2014 in Qiyang County (Hunan Province). Average topsoil pH declined of 0.58 units between the two surveys. Soil pH in the south was lower than in the north both in 1982 and 2014. Land use and parent materials are the main drivers of differences in the soil pH changes in Qiyang County. Soil pH declined significantly in forest and upland crop over non-alkaline parent materials during 1982-2014 period. Chemical N fertilizer application can have generated 12-42 kmol H+ ha-1yr-1, which is much higher than removal by crop harvest. Reduction of chemical N fertilization and return of straws to field should be conducted to reduce H+ production and supplement base cations in Qiyang County. The second approach studied evolution of inorganic P fractions in Red Soil under 25-year fertilization, and available P and inorganic P fractions responses to various soil acidity levels. Inorganic P fractions increased under P fertilization from 1990-2015, especially Ca2-P, Ca8-P and Al-P, but inorganic P fractions significantly decreased without P fertilization. Contributions of soil properties (SOC, C:P ratio and N:P ratio) and cumulative P apparent balance (CPAB) to inorganic P fractions were ≥ 95%, while interaction of CPAB and soil properties made greater contributions than did any single factor. Soil dissolved inorganic P (DIP) decreased with rising pH value, and a minimum DIP was observed between pH 5.5 and 6.5. Olsen-P, Ca-P and Al-P increased significantly with pH between 3.4 and 5.0. Soil with pH <5.0 P availability was much lower than soil with pH ≥5.0. Managing soil acidity is a key issue regarding availability of P in Red Soil of China and our results suggest that at least a pH of 5.0 should be targeted. [less ▲]

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