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See detailLong-range dispersion forces between molecules subject to attosecond pulses from ab initio calculations
Verstraete, Matthieu ULiege

Scientific conference (2017, July)

The London-van der Waals dispersion forces arising from instantaneously induced dipoles in molecules are a key ingredient in a wide range of phenomena in physics, chemistry, and biology. Therefore, the ... [more ▼]

The London-van der Waals dispersion forces arising from instantaneously induced dipoles in molecules are a key ingredient in a wide range of phenomena in physics, chemistry, and biology. Therefore, the ability to control and manipulate dispersion forces between atoms and molecules is of great importance. Because those dispersion interactions depend crucially on the electronic properties of the molecular systems, a simple route to achieve this would consist in manipulating their electronic states. The recent development of ultra-short optical pulses has given researchers unprecedented control over the electronic degrees of freedom. These pulses, tailored in their frequency and envelope, allow the generation of a strongly out of equilibrium population of electronic states. We show how the Hamacker constants characterizing the London-van der Waals interaction between two molecules subject to an optical pulse can be calculated using time-dependent density functional theory (TD-DFT) or standard quantum chemistry methods and present several test cases of molecules subjected to IR and UV attosecond pulses. [less ▲]

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See detailCrossoads ( juillet 2017) - chaque mercredi de 18h à20h - rediffusion: samedis de 22h à minuit
Sacré, Robert ULiege

Diverse speeche and writing (2017)

Programme radio hebdomadaire consacré aux musiques africaines-américaines ; streaming : www.equinoxefm.be ; podcasts www.mixcloud.com/robertsacre9

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See detailMonitoring of comets activity and composition with the TRAPPIST-North telescope
Moulane, Youssef ULiege; Benkhaldoun, Zouhair; Jehin, Emmanuel ULiege et al

in Journal of Physics: Conference Series (2017, July), 869

TRAPPIST-North (TRAnsiting Planets and PlanetesImals Small Telescope) is a 60-cm robotic telescope that was installed in May 2016 at the Oukaimeden Observatory. The project is led by the University of ... [more ▼]

TRAPPIST-North (TRAnsiting Planets and PlanetesImals Small Telescope) is a 60-cm robotic telescope that was installed in May 2016 at the Oukaimeden Observatory. The project is led by the University of Liège (Belgium) and the Caddi Ayad University of Marrakech (Morocco). This telescope is a twin of the TRAPPIST-South telescope, which was installed at the ESO La Silla Observatory in 2010. The TRAPPIST telescopes are dedicated to the detection and characterization of planets orbiting stars other than our Sun (exoplanets) and the study of comets and other small bodies in our solar system. For the comets research, these telescopes have very sensitive CCD cameras with complete sets of narrow band filters to measure the production rates of several gases (OH, NH, CN, C3 and C2) and the dust. With TRAPPIST-North we can also observe comets that would not be visible in the southern hemisphere. Therfore, with these two telescopes, we can now observe continuously the comets around their orbit. We project to study individually the evolution of the activity, chemical composition, dust properties, and coma morphology of several comets per year and of different origins (New comets and Jupiter Family comets) over a wide range of heliocentric distances, and on both sides of perihelion. We measure the production rates of each daughter molecules using a Haser model, in addition to the Afρ parameter to estimate the dust production in the coma. In this work, we present the first measurements of the production rates of comet C/2013 X1 (PANSTARRS) observed with TN in June 2016, and the measurements of comet C/2013 V5 (Oukaimeden) observed in 2014 with TRAPPIST-South. [less ▲]

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See detailBack to America: tracking the origin of European introduced populations of Quercus rubra L.
Merceron, Nastasia; Leroy, Thibault; Chancerel, Emilie et al

in Genome = Génome (2017), 60

Abstract: Quercus rubra has been introduced in Europe since the end of the 17th century. It is widely distributed today across this continent and considered invasive in some countries. Here, we ... [more ▼]

Abstract: Quercus rubra has been introduced in Europe since the end of the 17th century. It is widely distributed today across this continent and considered invasive in some countries. Here, we investigated the distribution of genetic diversity of both native and introduced populations with the aim of tracing the origin of introduced populations. A large sampling of 883 individuals from 73 native and 38 European locations were genotyped at 69 SNPs. In the natural range, we found a continuous geographic gradient of variation with a predominant latitudinal component. We explored the existence of ancestral populations by performing Bayesian clustering analysis and found support for two or three ancestral genetic clusters. Approximate Bayesian Computations analyses based on these two or three clusters support recent extensive secondary contacts between them, suggesting that present-day continuous genetic variation resulted from recent admixture. In the introduced range, one main genetic cluster was not recovered in Europe, suggesting that source populations were preferentially located in the northern part of the natural distribution. However, our results cannot refute the introduction of populations from the southern states that did not survive in Europe. [less ▲]

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See detailWEATHERING ON THE DEVONIAN SLATES AND CHARACTERIZATION OF A BENTONITE LAYER IN THE WESTERWALD (GERMANY)
Fontaine, François ULiege; Hamaekers, Helen; Hoffmann, Andreas et al

Conference (2017, July)

The Westerwald region is one of the largest and oldest clay mining areas of Germany. Those deposits were formed during the Eocene and Oligocene as a result of the weathering, erosion and redeposition of ... [more ▼]

The Westerwald region is one of the largest and oldest clay mining areas of Germany. Those deposits were formed during the Eocene and Oligocene as a result of the weathering, erosion and redeposition of Devonian rocks. During the Miocene, intense volcanic activities led to a large basalt cover, protecting the clays from the erosion. The two main goals of this study are first to improve the knowledge on the weathering processes of the Devonian slates that led to the current setting of those clay deposits by studying the mineralogical and chemical composition of the clays with depth. The second goal is to characterize a bentonite layer underneath the Miocene basalt cover using quantitative X-ray diffraction, chemical analysis, BET, cation exchange capacity and scanning electron microscope. A 20 meter deep quarry mining the Devonian bedrock in southern Westerwald has been sampled on its entire depth. The XRD results show no significant variations of the mineralogy with depth, except for the phyllosilicates. The minerals of the < 2 μm fraction are illite, kaolinite, smectite and mixed-layers minerals (vermiculite-chlorite and illite-chlorite). The proportions of the minerals in the mixed-layers chlorite-vermiculite vary with depth. At the bottom of the quarry, the proportion of vermiculite is very low while in the top, the proportion of vermiculite is higher. This is explained by the degree of the weathering, logically more intense at the top of the quarry. Trace elements compositions are currently being investigated. A 3 meter thick greenish to brownish bentonite layer has been found in the eastern part of the Westerwald region. The XRD performed on different samples of this bentonite shows a relatively heterogeneous composition: montmorillonite (60-80%), kaolinite (5-12%), illite (0-7%), goethite (2-15%), talc (0-10%), K-feldspars (0-7%), plagioclase (0-4%) and traces of amphibole and pyroxene. This bentonite is probably the result of the weathering of volcanic ashes. Since there are not many outcrops of this bentonite layer, its spatial distribution is studied by drilling. [less ▲]

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See detailCognitive brain responses during circadian wake-promotion: evidence for sleep- pressure-dependent hypothalamic activations
Reichert, Carolin Franziska; Maire, Micheline; Gabel, Virginie et al

in Scientific Reports (2017), 7(1),

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See detailViolences conjugales : un dilemme pour la justice pénale ? Leçons d’une analyse des enregistrements statistiques effectués dans les parquets belges
Vanneste, Charlotte ULiege

in Champ pénal/Penal field (2017), XIV

Drawing on the analysis of statistics regarding Intimate Partner Violence collected on a large scale at the level of the Belgian prosecutors’ offices, the article reveals a wide gap between the zero ... [more ▼]

Drawing on the analysis of statistics regarding Intimate Partner Violence collected on a large scale at the level of the Belgian prosecutors’ offices, the article reveals a wide gap between the zero tolerance rhetoric conveyed in the normative discourse and actual implementation, which is generally weak and showing divergent judicial practices in the field. Faced with this dilemma, the highly contestable impact of the zero tolerance policy observed in preventing recidivism offers a substantial argument to revisit the role of the criminal justice system in this area. [less ▲]

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See detailViolences conjugales et justice pénale
Glowacz, Fabienne ULiege; Vanneste, Charlotte ULiege

Book published by CNRS Revue.Org (2017)

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See detailRepresentations about physical activity among firefighters. A study in Wallonie
Dubru, Gilles ULiege; Gribomont, Antoine; Cloes, Marc ULiege

Poster (2017, July)

Introduction To be a firefighter is a dangerous job. Many authors have found anxiety, stress, depression, sleep disorders, absenteeism and other deviant behaviors in this type of high-risk occupation ... [more ▼]

Introduction To be a firefighter is a dangerous job. Many authors have found anxiety, stress, depression, sleep disorders, absenteeism and other deviant behaviors in this type of high-risk occupation (Fullerton, Ursano & Wang, 2004 ; Carey, Al-Zaiti, Dean, Sessanna & Finnell, 2011 ; Elliot & Kuehl, 2007). Adopting an active lifestyle is therefore very important in reducing these health risks and thus maximizing the chances of staying healthy. It is for this reason that physical activity has an essential role for these people. According to this determining the place occupied by physical activity within the regional Walloon fire servicesseemed relevant. The first step should be to analyse the firefighters’ representations and lifestyle. Methods An online questionnaire (SurveyMonkey) was developed. It proposed a majority of closed-ended questions facing on age (38 ± 10.4 years), BMI (26.1 ± 3.7), gender (96.7% of men), rank, status (38.3% professional), PA representations and practices, well-being and self-esteem, job satisfaction, … We contacted one of the main firefighters association (FRCSPB) to reach a significant number of topics. 443 questionnaires were collected during a five weeks period. 394 were usable. 376 responses were needed to achieve a 95% confidence level with a 5% confidence interval based on all Belgian Firefighter. Results and discussion Results showed that firefighter showed positive representations about PA and were aware of the benefits of a regular practice on their health. Good stress management and cardiovascular endurance qualities were considerate as important in this profession. Nevertheless, subjects deplored a lack of maintenance of these qualities. The mean BMI of the subjects was above 26, indicating a slight overweight. Sedentary lifestyle, poor infrastructure, injuries due to lack of fitness allow us to suspect an insufficient training. Other factors were pointed out by the subjects (stress, absenteeism, deviant behavior…). Firefighters were generally satisfied with their job and considered that they have an acceptable quality of life. However lack of time, financial and human resources must not be a barrier to the practice of essential PA for those people who are directly related with danger. References Carey, M. G., Al-Zaiti, S. S., Dean, G. E., Sessanna, L., & Finnell, D. S. (2011). Sleep problems, depression, substance use, social bonding, and quality of live in professional firefighters. The international journal of occupational and environmental medicine, 53(8), 928-933. Doi: 10.1097/JOM.0b013e318225898f. Elliot, D. L., & Kuehl, K.S. (2007). The effects of sleep deprivation on firefighters and EMS responders: final report. International Association of fire Chiefs. Fullerton, C. S., Ursano, R.J.,& Wang, L. (2004). Acute stress disorder, posttraumatic stress disorder, and depression in disaster or rescue workers. The American Journal of Psychiatry, 161(8), 1370-76. [less ▲]

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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 detailNet neutrality: Paid prioritization vs Zero-rating
Gautier, Axel ULiege

Conference (2017, July)

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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 CAAD Futures 2017 (2017)

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 detailAverage first-passage time of a quasi-Hamiltonian Mathieu oscillator with parametric and forcing excitations
Vanvinckenroye, Hélène ULiege; Denoël, Vincent ULiege

in Journal of Sound and Vibration (2017)

A linear oscillator simultaneously subjected to stochastic forcing and parametric excitation is considered. The time required for this system to evolve from a low initial energy level until a higher ... [more ▼]

A linear oscillator simultaneously subjected to stochastic forcing and parametric excitation is considered. The time required for this system to evolve from a low initial energy level until a higher energy state for the first time is a random variable. Its expectation satisfies the Pontryagin equation of the problem, which is solved with the asymptotic expansion method developed by Khasminskii. This allowed deriving closed-form expressions for the expected first passage time. A comprehensive parameter analysis of these solutions is performed. Beside identifying the important dimensionless groups governing the problem, it also highlights three important regimes which are called incubation, multiplicative and additive because of their specific features. Those three regimes are discussed with the parameters of the problem. [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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