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Multivariate Approach to Characterizing Soil Quality of gabonese’s Ferralitic Soils

Open Journal of Soil Science 2024年第4期14卷 237-268页

作者： Neil-Yohan Musadji Rolf gaël Mabicka Obame Michel Mbina Mounguengui Jean Aubin Ondo Lydie-Stella Koutika Eric Ravire Claude geffroy Laboratoire de Chimie Des Milieux et Des Mat&#233riaux Inorganiques Laboratoire D&#8217Analyse Des Sols et Environnement D&#233partement Des Sciences Fondamentales De L&#8217Ing&#233nieur Institut National D&#8217Agronomie et De Biotechnologies Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Institut de Chimie des Milieux et Maté riaux De Poitiers (IC2MP) Universit&#233 De Poitiers Poitiers France Laboratoire de Chimie Des Milieux et Des Mat&#233riaux Inorganiques Laboratoire D&#8217Analyse Des Sols et Environnement D&#233partement De Phytotechnologie Institut National D&#8217Agronomie et De Biotechnologies Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon dé partement De G&#233ologie Facult&#233 Des Sciences Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Laboratoire Pluridisciplinaire des Sciences Ecole Normale Sup&#233rieure Libreville Gabon Centre de Recherche Sur La Productivité et La Durabilit&#233 Des Plantations Industrielles Pointe Noire Republic of Congo Sucaf gabon Somdiaa Franceville Gabon

Assessing soil quality is essential for crop management and soil temporal changes. The present study aims to evaluate soil quality in the Ferralitic soils context countrywide. This assessment was done using multivariate soil quality indice (SQI) models, such as additive quality index (AQI), weighted quality indexes (WQIadd and WQIcom) and Nemoro quality index (NQI), applied to two approaches of indicator selection: total data set (TdS) and minimum data set (MdS). Physical and chemical soil indicators were extracted from the ORSTOM’s reports resulting from a sampling campaign in different provinces of gabon. The TdS approach shows soil quality status according to eleven soil indicators extracted from the analysis of 1,059 samples from arable soil layer (0 - 30 cm depth). The results indicated that 87% of all provinces presented a very low soil quality (Q5) whatever the model. Among soil indicators, exchangeable K+ and Mg2+, bulk density and C/N ratio were retained in MdS, using principal component analysis (PCA). In the MdS approach, 50 to 63% of provinces had low soil quality grades with AQI, WQIadd and NQI, whereas the total was observed with WQIcom. Only 25% of provinces had medium soil quality grades with AQI and NQI models, while 12.5% (NQI) and 25% (AQI) presented high quality grades. Robust statistical analyses confirmed the accuracy and validation (0.80 r P ≤ 0.016) of AQI, WQIadd and NQI into the TdS and MdS approaches. The same sensitivity index value (1.53) was obtained with AQI and WQIadd. However, WQIadd was chosen as the best SQI model, according to its high linear regression value (R2 = 0.82) between TdS and MdS. This study has important implications in decision-making on monitoring, evaluation and sustainable management of gabonese soils in a pedoclimatic context unfavorable to plant growth.

关键词： gabon Ferralitic Soil Soil Indicators Standard Score Function Soil Quality Indices Sustainable Soil Soil Management

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Comparative Study between dielectric Properties and Compaction Parameters: Case Study on Three Laterite Quarries

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Open Journal of geology 2024年第8期14卷 746-759页

作者： Cheikh diallo diene Sabou Sarr Abdoulaye Cissé Mapathé Ndiaye Laboratoire de gophysique UFR Sciences de lIngnieur University Iba Der Thiam Thies Senegal Laboratoire de Modlisation et de Mcanique des sols UFR Sciences de lIngnieur University Iba Der Thiam Thies Senegal

This work studies the variability of the relationship between relative permittivity and compaction parameters as a function of certain geotechnical properties for different laterite types. This study allows to purpose the dielectric permittivity as a third compaction parameter allowing to obtain a non destructive control méthod. Preliminary studies on diack laterite had shown a good correlation. Additional investigations are carried out to verify the possibility of generalizing this correlation to three new laterite careers: Ngoudiane, Yéba and Fandene. To proceed, particle size analysis, Atterberg limits, specific weight tests and compaction according to the modified Proctor test were performed on laterite samples. Using the radar method, experimental permittivities are determined for laterite samples by the point method of propagation times and confirmed by the diffraction hyperbole method. The geotechnical and radar data obtained allowed correlations between permittivity and water content on the one hand and between permittivity and dry density on the other. The results show that the maximum dry density as a function of permittivity corresponds with the optimum Proctor, which confirms the results previously obtained on diack laterite.

关键词： Radar Laterite Moisture Content dry density Permittivity geotechnical Properties

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Effects of accelerating and decelerating flows in a channel with vegetated banks and gravel bed

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International Journal of Sediment Research 2012年第2期27卷 188-200页

作者： Hossein AFZALIMEHR Elham Fazel NAJAFABAdI Jacques gALLICHANd department of Water Engineering Isfahan University of Technology84156-83111Iran dpartement des sols et de gnie agroalimentaire Pavilion Paul-Comtois Universit LavalSt-FoyQCCanada

Experiments were conducted in an 8 m long,40 cm wide,and 60 cm deep re-circulating flume with vegetated banks and gravel bed to study the effects of accelerating and decelerating flows on the flow *** dip phenomenon was observed in velocity profiles under decelerating flow and the velocity defect law was not suitable due to the effect of vegetated *** the vegetated banks, the turbulence intensities illustrated convex distribution for both accelerating and decelerating flows. Application of quadrant analysis revealed that the effect of vegetated banks is important on the flow structure and the Reynolds stress *** and decelerating flows did not show a significant difference on percentage of time occupied by each kind of turbulent event within bursting cycle,but affected the shape of joint probability distributions of turbulent intensities in the horizontal and vertical directions.

关键词： Vegetated bank decelerating and accelerating flows gravel bed Reynolds stress

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Contamination,Fractionation and Availability of Metals in Urban Soils in the Vicinity of Former Lead and Zinc Smelters,France

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Pedosphere 2013年第2期23卷 143-159页

作者： C.WATERLOT g.BIdAR A.PELFRNE H.ROUSSEL H.FOURRIER F.dOUAY Université Lille Nord de France groupe ISA Equipe Sols et Environnement Laboratoire Génie Civil et géoEnvironnement (LGCgE) Lille Nord de France (EA 4515) département des Sites et sols Pollués Agence de I'Environment et de la Matrise de I'Energie (ADEME)

Soil contamination by metals from anthropogenic activities （e.g., mining and smelting） is a major concern for the environment and human health. Environmental availability of cadmium （Cd）, lead （Pb）, zinc （Zn）, copper （Cu）, and indium （In） in 27 urban soils located around two former Pb and Zn smelters in Northern France were studied by analysing the chemical forms of these metals and evaluating their phytoavailability. These metals were determined using flame or electrothermal absorption atomic spectrometry （FAAS or etAAS）, depending on their concentration levels. After optimisation of the etAAS method, characteristic mass of In in water and aqua regia were 9.9 and 18 pg, respectively, showing the high sensitivity of the analytical procedure. Metal partitioning was conducted using a four-step sequential extraction procedure. The results showed that Cd and Zn were mainly in the acid-extractable and reducible forms in the urban soils studied. In contrast, Pb and In were largely in the reducible fraction. However, in some samples, the amount of In extracted in the residual or exchangeable fraction was higher than that in the reducible fraction. Copper was mainly found in the reducible and residual fractions. A pot experiment was conducted in a glasshouse with seven soils （six contaminated and one uncontaminated） and two plant species, ryegrass and lettuce. The results showed transfer of metals from the contaminated soils to the shoots of ryegrass and the edible part of lettuce. The metal bioconcentration factor was in the order of Cd 〉〉 Cu 〉 In 〉 Zn 〉〉 Pb for lettuce leaves, whereas for ryegrass shoots, three orders were found, Cd 〉 Zn 〉 Cu 〉〉 In 〉 Pb, Cd 〉〉 In 〉 Zn 〉 Cu 〉〉Pb, and Zn 〉 Cd 〉 Cu 〉 In 〉〉 Pb, depending on the physico-chemical properties of the soils, such as pH, cation exchange capacity, carbonates, and organic matter. It was established that the metal toxicity was related to the contamination levels and the physico-chemical properties, including pH, organi

关键词： bioconcentration factor environmental availability metal toxicity sequential extraction soil physico-chemical property

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Positioning Temperature Sensors for Frost Protection in Northern Cranberry Production

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Agricultural Sciences 2017年第9期8卷 960-971页

作者： Vincent Pelletier Silvio Jose gumiere Steeve Pepin Jacques gallichand Jean Caron département des sols et de génie agroalimentaire Université Laval Québec Canada

Frost can cause serious economic losses in cranberry fields, particularly in northern regions. When the air temperature reaches a low critical threshold, sprinklers are operated to protect vines, to insure crop production and profitability. To avoid frost injury, proper positioning of temperature sensors is critical. A field experiment was designed and conducted to determine the optimal installation height of sensors above soil surface. Temperature data was used to investigate the spatial temperature gradient in the section of a cranberry field. A computer simulation of the temperature profile was performed to simulate the effect of wind velocity on the prediction of air temperature. For optimal use, sensors should be installed at the height of the canopy and several meters away from a dike. On nights with low wind velocities, the canopy air temperature was 2.7°C below that of 500 cm above the ground. The sensors should be put at least five m away from a dike to avoid the transfer of heat from the dike to the sensor. Also, multiple sensors should be installed because of the large variations in air temperature that were measured across the experiment. The simulated temperature indicated that wind velocity strongly influenced the temperature estimation;the effect of the wind on temperatures gradients was greater when the wind velocity was low (<2.3 m/s).

关键词： Frost Protection Cranberry Production Numerical Simulation of Heat Transfer

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Effect of vegetated-banks on local scour around a wing-wall abutment with circular edges

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Journal of Hydrodynamics 2014年第3期26卷 447-457页

作者： AFZALIMEHR Hossein BAKHSHI Somayeh gALLICHANd Jacques SUI Jueyi department of Water Engineering Isfahan University of Technology Isfahan Iran department des sols et de génie agroalimentaire Pavillon Paul-Comtois Université Laval St-Foy QC Canada Environmental Engineering program University of Northern British Colombia Prince George BC Canada

Failure of bridges due to local scour in the vicinity of bridge abutments is a common occurrence. In this study, experiments under two different channel conditions were conducted to assess the impacts of vegetation on channel banks on local scour around a wing-wall abutment with circular edges. Some experiments were conducted in channel with vegetation on channel banks, and other experiments in channel without vegetation on channel bank. The flow velocity and Reynolds stress distributions in scour holes around a wing-wall abutment with circular edges were compared under these 2 different channel conditions. Results reveal that the vegetated-banks can reduce the time for achieving the equilibrium condition from 17 h to 9 h. Also, vegetated-bank channels can result in a significant decrease in the maximum scour depth from 0.084 m（for bare channel bank） to 0.00032 m. Additionally, around the abutment, vegetated-banks play a significant role in diminishing the Reynolds stress（RS） near the bed and removing negative values in RS distribution by weakening unfavorable pressure gradient and down-flow in the upstream of abutment.

关键词： local scour vegetated-banks wing-wall abutment circular edges Reynolds stress(RS)

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Field investigation on friction factor in mountainous cobble-bed and boulder-bed rivers

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International Journal of Sediment Research 2011年第2期26卷 210-221页

作者： Hossein AFZALIMEHR Jacques gALLICHANd Ehsan BAgHERI department of Water Engineering Isfahan University of Technology departement des sols et de genie agroalimentaire Universite Laval Water Engineering department Isfahan University of Technology

This paper presents results of the friction factor of cobble-bed and boulder-bed rivers based on 23 field measurements in three mountainous rivers in *** reveal that features of our measured velocity profiles in boulder-bed rivers in mountainous region do not present a specific shape but illustrate specific pattern in cobble-bed *** difference is attributed to scale effect of relative submergence. It is found that the relative submergence in cobble and boulders-bed rivers is the only key parameter that influences friction factor estimation and other parameters such as particle Froude number and Froude number have few impacts on flow resistance of cobble-bed and boulder-bed *** proposed relationship for estimation for the friction factor should be useful for large coarse-bed rivers.

关键词： Boulder-bed Cobble-bed Friction factor Mountainous river Relative submergence

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Investigation of turbulence characteristics in channel with dense vegetation

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International Journal of Sediment Research 2011年第3期26卷 269-280+282+281页

作者： Hossein AFZALIMEHR Razieh MOgHBEL Jacques gALLICHANd Water Engineering department Isfahan University of TechnologyIran 84156 departement des sols et de genie agroalimentaire Universite LavalSt-FoyQcCanada

In this experimental study,the turbulent flow in a channel with vegetation by using sprouts of wheat on channel bed was *** different aspect ratios of channel were *** Acoustic doppler Velocimetry was used to measure parameters of turbulent flow over submerged sprouts of wheat,such as velocity *** log law and the Reynolds shear stress distribution were applied. Results indicate that the position of the maximum turbulence intensity superposes on the inflection point situated over the top of submerged vegetation *** analysis shows that near the vegetation bed,the sweeps and ejections appear to be the most dominant phenomenon,while far from the vegetated bed,the outward is dominant *** also show that the aspect ratio plays an important role on the contribution of the different bursting events for Reynolds stress determination.

关键词： Bed vegetation Aspect ratio Reynolds stress Quadrant analysis

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Soil Contamination due to E-Waste disposal and Recycling Activities: A Review with Special Focus on China

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Pedosphere 2012年第4期22卷 470-488页

作者： g. ECHEVARRIA T. STERCKEMAN M. O. SIMONNOT J. L. MOREL INPL(ENSAIA)/INRA Laboratoire Sols et Environnement 2 Avenue de la For et de Haye BP 172 54505 Vandoeuvre-lès-Nancy Cedex (France) Laboratoire Réactions et génie des Procédés (LRgP) Université de Lorraine-CNRS (UPR 3349) 1 Rue Grandville BP20451 54001 Nancy Cedex (France)

Considering that even contaminated soils are a potential resource for agricultural production, it is essential to develop a set of cropping systems to allow a safe and sustainable agriculture on contaminated lands while avoiding any transfer of toxic trace elements to the food chain. In this review, three main strategies, i.e., phytoexclusion, phytostabilization, and phytoextraction, are proposed to establish cropping systems for production of edible and non-edible plants, and for extraction of elements for industrial use. For safe production of food crops, the selection of low-accumulating plants/cultivars and the application of soil amendments are of vital importance. Phytostabilization using non-food energy and fiber plants can provide additional renewable energy sources and economic benefit with minimum cost of agricultural measures. Phytoextracting trace elements （e.g., As, Cd, Ni, and Zn） using hyperaccumulator species is more suitable for slightly and moderately polluted sites, and phytomining of Ni from serpentine soils has shown a great potential to extract Ni-containing bio-ores of economic interests. We conclude that appropriate combinations of soil types, plant species/cultivars, and agronomic practices can restrict trace metal transfer to the food chain and/or extract energy and metals of industrial use and allow safe agricultural activities.

关键词： agronomic practices food safety hyperaccumulator phytoremediation trace element

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Natural hydroxyanthraquinoid pigments as potent food grade colorants:an overview

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Natural Products and Bioprospecting 2012年第5期2卷 174-193页

作者： Yanis CARO Linda ANAMALE Mireille FOUILLAUd Philippe LAURENT Thomas PetIT Laurent dUFOSSE département agroalimentaire ESIROIUniversitéde La RéunionSainte-ClotildeIle de la RéunionFrance LCSNSA Facultédes Sciences et des TechnologiesUniversitéde La RéunionSainte-ClotildeIle de la RéunionFrance département génie Biologique IUTUniversitéde La RéunionSaint-PierreIle de la RéunionFrance

Natural pigments and colorants are widely used in the world in many industries such as textile dying,food processing or cosmetic *** the natural products of interest are various compounds belonging to carotenoids,anthocyanins,chlorophylls,melanins,betalains...The review emphasizes pigments with anthraquinoid skeleton and gives an overview on hydroxyanthraquinoids described in Nature,the first one ever *** in consumption,production and regulation of natural food grade colorants are given,in the current global *** second part focuses on the description of the chemical structures of the main anthraquinoid colouring compounds,their properties and their biosynthetic *** natural sources of such pigments are summarized,followed by discussion about toxicity and carcinogenicity observed in some *** a conclusion,current industrial applications of natural hydroxyanthraquinoids are described with two examples,carminic acid from an insect and Arpink red^(™)from a filamentous fungus.

关键词： anthraquinone hydroxyanthraquinone natural colorant food colorant microbial pigment biotechnology mycotoxin contamination

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