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Are diurnal time-budgets and activity patterns density-dependent in the Shelduck (Tadorna tadorna) wintering in Algeria? An analysis across multiple temporal scales

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Avian Research 2019年第2期10卷 171-185页

作者： Djamel Bensizerara haroun chenchouni Department of Biology Faculty of Nature and Life SciencesUniversity of Abbes Laghrour40000 KhenchelaAlgeria Department of Natural and Life Sciences Faculty of Exact Sciences and Natural and Life SciencesUniversity of Tebessa12002 TebessaAlgeria Laboratory of Natural Resources and Management of Sensitive Environments 'RNAMS’ University of Oum-El-Bouaghi04000 Oum-El-BouaghiAlgeria

Background: The Shelduck (Tadorna tadorna) is a characteristic waterbird species of inland wetlands in northeastern Algeria. Its wintering behavior in relation to changes of local abundances and foraging group density is poorly known. Objectives: This study aims at monitoring patterns of diurnal activities and the variation of behavioral time-budgets in relation to numbers of wintering Shelducks. We investigate temporal variations of diurnal activities across multipletime scales and consider their interrelationships. Methods: Assessments of local population abundance were weekly surveyed during two wintering seasons (2010– 2012), whereas diurnal activities (feeding, sleeping, swimming, preening, loafing, flying, courtship, and antagonism) were studied three times a month during seven hours (08:00–16:00) using the Scan method. Time budget variations of each behavioral activity were tested using nested ANOVAs following multiple time scales. Generalized linear mixedeffects models (GLMM) tested whether variations in diurnal activities were density-dependent. Results: During the wintering season, Shelduck’s numbers followed a bell-shaped trend, which indicated that the species was typically a wintering migrant in Sabkha Djendli. The first individuals arrived onsite in October–November then numbers reached a peak in January (up to 2400 individuals in 2012) with steady density during December–February, afterward individuals left the site progressively until late April when the site is deserted. During both wintering seasons, diurnal activities were dominated by feeding (60%), followed by sleeping (12%) then swimming and preening with 9% and 8%, respectively. The rest of the activities (loafing, flying, courtship and antagonistic behaviors) had low proportions of time budget. ANOVAs showed that activity time budgets varied significantly following multiple time scales (year, season, month, day, semi-hour). Time budgets of diurnal activities during each wintering season were

关键词： Anatidae Multi-temporal scales North African wetlands Time budget Waterbird census

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Thriving green havens in baking deserts:Plant diversity and species composition of urban plantations in the Sahara Desert

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Journal of Arid Land 2024年第9期16卷 1270-1287页

作者： Mohammed SOUDDI haroun chenchouni M'hammed BOUALLALA Laboratory of Saharan Natural Resources Faculty of Nature and Life SciencesUniversity of Ahmed Draia-AdrarAdrar 01000Algeria Laboratory of Algerian Forests and Climate Change Higher National School of ForestsKhenchela 40000Algeria Laboratory of Natural Resources and Management of Sensitive Environments University of Oum El BouaghiOum El Bouaghi 04000Algeria Higher School of Saharan Agriculture Adrar 01000Algeria

Hot arid zones represent vital reservoirs of unique species and ecosystems,holding significant importance for *** study aimed to explore the plant diversity associated with tree plantations in urban ecosystems under hyper-arid climatic conditions in the Sahara Desert of *** May 2022,30 quadrats measuring 1 m^(2) each were established at the base of Phoenix dactylifera,Leucaena leucocephala,and Tamarix aphylla,corresponding to the dominant tree species in each of three *** each quadrat,the plant quantitative inventory was conducted to measure plant diversity and similarity among the studied *** on this,we assessed the plant functional traits and rarity/abundance status of the *** findings revealed a diverse flora associated with the studied plantations,comprising 29 plant species grouped into 27 genera and 12 ***,Poaceae(accounting for 30.8% of the flora),Asteraceae(25.0%),and Zygophyllaceae(21.6%)were *** an overall density of approximately 555 individuals/m^(2),Zygophyllum album(120 individuals/m^(2))and Polypogon monspeliensis(87 individuals/m^(2))emerged as the most abundant *** trait analysis underscored the pivotal role of therophytes(constituting over 50.0% of the flora)and anemochorous species(33.0%-62.5%).Phytogeographic analysis emphasized the prevalence of the Saharo-Arabic element(constituting over 31.0% of the flora)and the Mediterranean Saharo-Arabic element(9.5%-21.5%).The Cosmopolitan element thrived under disturbance factors,recording percentages from 13.0% to 20.0% of the plant *** rarity/abundance status of the flora emphasized the significance of rare,common,and very common species in the studied *** findings could provide fundamental data for the effective control and management of biodiversity in hot hyper-arid urban ecosystems.

关键词： urban plantations plant diversity plant functional traits rarity/abundance status Sahara Desert Algeria

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Do aeolian deposits and sand encroachment intensity shape patterns of vegetation diversity and plant functional traits in desert pavements?

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Journal of Arid Land 2023年第6期15卷 667-694页

作者： M'hammed BOUALLALA Souad NEFFAR Lyès BRADAI haroun chenchouni Laboratory of Saharan Natural Resources Faculty of Sciences and TechnologyUniversity of Ahmed DraiaAdrar 01000Algeria Department of Nature and Life Sciences Faculty of Exact Sciences and Nature and Life SciencesUniversity of TebessaTebessa 12002Algeria Laboratory Water and Environment University of TebessaTebessa 12002Algeria Laboratory of Saharan Bioresources Preservation and Valorization Faculty of Nature and Life SciencesUniversity of Kasdi MerbahOuargla 30000Algeria Department of Forest Management Higher National School of ForestsKhenchela 40000Algeria Laboratory of Natural Resources and Management of Sensitive Environments University of Oum-El-BouaghiOum-El-Bouaghi 04000Algeria

The effects of sand encroachment on composition,diversity,and functional patterns of vegetation in drylands are rarely studied,and yet addressing these aspects is important to deepen our understanding of the biodiversity *** study aimed to investigate the effect of sand encroachment on plant functional biodiversity of desert pavements(gravel deserts)in the Sahara Desert of *** were sampled and analyzed in three desert pavements with different levels of sand encroachment(LSE)and quantity of aeolian deposits(low,LLSE;medium,MLSE;and high,HLSE).Within the sample-plot area(100 m^(2)),density of every plant species was identified and total vegetation cover was *** taxonomic and functional diversity were analyzed and compared between *** showed that 19 plant species in desert pavements were classified into 18 genera and 13 *** and Poaceae were the most important *** species Anabasis articulata(Forssk)*** LLSE desert pavements with 11 species,whereas Thymelaea microphylla Coss.&Durieu ex *** Calobota saharae(C&D)Boatwr.&van Wyk were dominant species of desert pavements with MLSE(14 species)and HLSE(10 species),*** highest values of species richness and biodiversity were recorded in desert pavements with MLSE,while low values of these ecological parameters were obtained in desert pavements with *** pavements with LLSE were characterized with the highest values of species *** communities were dominated by chamaephytes,anemochorous,arido-active,and competitive stress-tolerant *** increase in LSE along the gradient from LLSE to HLSE induced significant changes in plant community variables including decreases in plant density,plant rarity,lifeform composition,morphological type,and aridity *** pavements with HLSE favor the degradation of vegetation and trigger biodiversity erosion.

关键词： desert pavements hot and arid rangeland plant diversity land degradation sand encroachment plant functional trait Sahara Desert

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Does melanin-based plumage coloration reflect health status of free-living birds in urban environments?

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Avian Research 2021年第4期12卷 553-568页

作者： Hani Amir Aouissi Mostefa Ababsa Aissam Gaagai Zihad Bouslama Yassine Farhi haroun chenchouni Scientific and Technical Research Center on Arid Regions(CRSTRA) 07000 BiskraAlgeria Faculty of Sciences Department of BiologyBadji-Mokhtar Annaba University23000 AnnabaAlgeria Environmental Research Center(CRE) Badji-Mokhtar Annaba University23000 AnnabaAlgeria Department of Nature and Life Sciences Faculty of Exact Sciences and Nature and Life SciencesUniversity of Larbi Tebessi12002 TebessaAlgeria Labora-tory of Natural Resources and Management of Sensitive Environments‘RNAMS’ University of Larbi Ben M’hidi04000 Oum-El-BouaghiAlgeria

Background:Ecological functions and processes in urban ecosystems are governed by various human ***-adapted and city-exploiting animal species are expected to present certain specific behavioral and physiological traits in comparison to city-avoiders or conspecific individual frequenting less urbanized or rural environments.A trait of high importance,the plumage color polymorphism has been selected as the main study model and was correlated with different morphological and physiological parameters to highlight its importance in determining the possible health status of urban Feral Pigeons(Columba livia)in North African urban ***:Different body morphometrics,hematological and hemoparasitic parameters were quantified on freeliving Feral Pigeons in urban environments of northern ***,plumage melanin-based coloration(MBC)was measured and the data collected at the individual scale was correlated with the previous parameters using linear and non-linear modeling ***:Plumage MBC scores of the sampled Feral Pigeons ranged between 0.3%and 74.8%.Among the 12 morphological traits measured,body weight,tail length and total length were deemed to be positively correlated with *** morphs appeared to have more hemoparasites compared to lighter *** the same observation goes with the immunity but with non-linear *** number of monocytes and granulocytes increased with the increase in MBC levels in lighter morphs,while pigeons with high MBC scores exhibited negative relationships between MBC levels and the number of white blood ***:Despite the existence of a number of studies demonstrating phenotypic directional selection,further studies are undoubtedly necessary to understand in detail the underlying mechanisms in species life-history strategies between differently colored *** of this correlative study open exciting perspectives revealing that MBC can be considered a good indicato

关键词： Columba livia Feather color polymorphism Feral birds Hematological indicators Hemoparasitism Immune ecophysiology Urbanization Urban ornithology

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Rapid increase in numbers and change of land-use in two expanding Columbidae species(Columba palumbus and Streptopelia decaocto)in Algeria

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Chinese Birds 2015年第4期6卷 246-254页

作者： Djamel Bendjoudi Jean-Francois Voisin Salaheddine Doumandji Amel Merabet Nassima Benyounes haroun chenchouni Department of Biology of Populations and Organisms Faculty of Natural and Life SciencesUniversity of Blida Muséum National d’Histoire Naturelle Department of Agricultural and Forestry Zoology National Superior School of Agronomy(ENSA)-El Harrach Department of Biology Faculty of SciencesUniversity of M’Hamed Bougara Department of Natural and Life Sciences Faculty of Exact Sciences and Natural and Life SciencesUniversity of Tebessa Department of Natural and Life Sciences Faculty of SciencesUniversity of El Hadj Lakhdar

Background: Investigating population ecology of urban bird species,particularly the invasive and expending spe?cies,is the key for the success of urban management and planning ***: Populations of two Columbidae species,the Woodpigeon(Columba palumbus) and the Eurasian Collared Dove(Streptopelia decaocto),were monitored from 1992 to 2010 in the Algiers Sahel,the Mitidja Plain and surround?ing areas(Northern Algeria).Monitoring of species densities was performed by the mapping?plot *** foraging flight routes of Woodpigeon and the distribution of Eurasian Collared Dove were assessed by systematic ***: The number of counted birds was statistically constant at first years of the survey,and then increased sig?nificantly,beginning from low numbers,their densities accelerated sharply between 2001 and 2006,then reached to an equilibrium *** significant increase in Woodpigeon's population could be explained by the reduced hunt?ing pressure and by species adaptation to new food resources provided by nearby ***,monitoring of flight directions of the species revealed the use of agricultural landscapes and habitats,which is a good indicator explaining adaptation and trophic niche of the *** occurrence of the Eurasian Collared Dove in Algiers began in *** density experienced a rapid increase with similar trend pattern as that of *** distributional range is confined mainly in suburban environments of the Mitidja ***: The modifications of habitats,urbanization increase and the lessening of hunting in the Mitidja Plain facilitated the rapid expansion of the Eurasian Collared Dove and Woodpigeon as well contributed to the increase in their numbers over time.

关键词： Columba palumbus Flight routes Mitidja plain Population dynamics Streptopelia decaocto

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Exploring groundwater quality in semi-arid areas of Algeria:Impacts on potable water supply and agricultural sustainability

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Journal of Arid Land 2024年第2期16卷 147-167页

作者： Noua ALLAOUA Hinda HAFID haroun chenchouni Laboratory of Natural Resources and Management of Sensitive Environments Larbi Ben M'hidi UniversityOum-El-Bouaghi 04000Algeria Department of Nature and Life Sciences Faculty of Exact Sciences and Nature and Life SciencesLarbi Ben M'hidi UniversityOum-El-Bouaghi 04000Algeria Laboratory of Algerian Forests and Climate Change Higher National School of ForestsKhenchela 40000Algeria

Groundwater quality assessment is important to assure safe and durable water *** semi-arid areas of Algeria,groundwater represents the main water resource for drinking water supply of the rural population as well as for irrigation of agricultural *** samples from wells and springs were collected from the Gargaat Tarf and Annk Djemel sub-watersheds of the Oum El Bouaghi,Algeria,and were analyzed and compared with the World Health Organization(WHO)*** showed that most of the measured physical and chemical parameters exceeded the quality limits according to the WHO *** had a slightly alkaline water pH(7.00-7.79),electrical conductivity>1500μS/cm,chloride>500 mg/L,calcium>250 mg/L,and magnesium>155 mg/*** quality index(WQI)results showed that 68%of the area had excellent water quality,24%of the samples fell into good category,and only 8%were of poor quality and unsuitable for human *** wells in the area showed bacterial *** coliforms(453.9(±180.3)CFU(colony-forming units)/100 mL),fecal coliforms(243.2(±99.2)CFU/100 mL),and fecal streptococci(77.9(±32.0)CFU/100 mL)loads were above the standard limits set by the *** results confirmed that water resources in the study area were strongly influenced by anthropogenic activities and were not recommended for consumption as drinking water.

关键词： bacteriological indicator groundwater watershed physical-chemical parameter water quality index

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Optimization study of a PEM fuel cell performance using 3D multi-phase computational fluid dynamics model

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第2期8卷 285-300页

作者： AL-BAGHDADI Maher A.R. Sadiq AL-JANABI haroun A.K.Shahad Department of Mechanical Engineering International Technological University

An optimization study using a comprehensive 3D, multi-phase, non-isothermal model of a PEM （proton exchange membrane） fuel cell that incorporates significant physical processes and key parameters affecting fuel cell performance is presented and discussed in detail. The model accounts for both gas and liquid phase in the same computational domain, and thus allows for the implementation of phase change inside the gas diffusion layers. The model includes the transport of gaseous species, liquid water, protons, energy, and water dissolved in the ion-conducting polymer. Water is assumed to be exchanged among three phases： liquid, vapottr, and dissolved, with equilibrium among these phases being assumed. This model also takes into account convection and diffusion of different species in the channels as well as in the porous gas diffusion layer, heat transfer in the solids as well as in the gases, and electrochemical reactions. The results showed that the present multi-phase model is capable of identifying important parameters for the wetting behaviour of the gas diffusion layers and can be used to identify conditions that might lead to the onset of pore plugging, which has a detrimental effect on the fuel cell performance. This model is used to study the effects of several operating, design, and material parameters on fuel cell performance. Detailed analyses of the fuel cell performance under various operating conditions have been conducted and examined.

关键词： Optimization PEM fuel cell Multi-phase Water transport CFD (computational fluid dynamics)

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Effects of magnetic field,porosity,and wall properties for anisotropically elastic multi-stenosis arteries on blood flow characteristics

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Applied Mathematics and Mechanics(English Edition) 2011年第8期32卷 1047-1064页

作者： Kh.S.MEKHEIMER M.H.haroun M.A.ELKOT Department of Mathematics Faculty of Science Al-Azhar University Department of Mathematics Faculty of Education Ain Shams University Department of Mathematics Faculty of Science Suez Canal University

A mathematical model for blood flow through an elastic artery with multistenosis under the effect of a magnetic field in a porous medium is presented. The considered arterial segment is simulated by an anisotropically elastic cylindrical tube filled with a viscous incompressible electrically conducting fluid representing blood. An artery with mild local narrowing in its lumen forming a stenosis is analyzed. The effects of arterial wall parameters represent viscoelastic stresses along the longitudinal and circumferential directions T t and T θ , respectively. The degree of anisotropy of the vessel wall γ, total mass of the vessel, and surrounding tissues M and contributions of the viscous and elastic constraints to the total tethering C and K respectively on resistance impedance, wall shear stress distribution, and radial and axial velocities are illustrated. Also, the effects of the stenosis shape m, the constant of permeability κ, the Hartmann number Ha and the maximum height of the stenosis size δ on the fluid flow characteristics are investigated. The results show that the flow is appreciably influenced by surrounding connective tissues of the arterial wall motion, and the degree of anisotropy of the vessel wall plays an important role in determining the material of the artery. Further, the wall shear stress distribution increases with increasing T t and γ while decreases with increasing T θ , M, C, and K. Transmission of the wall shear stress distribution and resistance impedance at the wall surface through a tethered tube are substantially lower than those through a free tube, while the shearing stress distribution at the stenosis throat has inverse characteristic through totally tethered and free tubes. The trapping bolus increases in size toward the line center of the tube as the permeability constant κ increases and decreases with the Hartmann number Ha increased. Finally, the trapping bolus appears, gradually in the case of non-symmetric stenosis, and disap

关键词： stenosis degree of anisotropy free tube tethered tube trapping bolus

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Design and Analysis of Potential Energy Recovery Hydraulic Tumping Unit

Design and Analysis of Potential Energy Recovery Hydraulic T...

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作者： haroun HASSAN IBMHIM 东北大学

学位级别：硕士

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Dietary effects of A zolla pinnata combined with exogenous digestive enzyme(Digestin^(TM)) on growth and nutrients utilization of freshwater prawn, Macrobrachium rosenbergii(de Man 1879)

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Journal of Oceanology and Limnology 2018年第4期36卷 1434-1441页

作者： GODA Ashraf SAAD Amal HANAFY Mohamed SHARAWY Zaki EL-haroun Ehab Aquaculture Division National Institute of Oceanography and Fisheries (NIOF) Institute of Oceanology Chinese Academy of Sciences Division of Aquaculture College of Agriculture Food Science and Sustainable Systems Kentucky State University

The present study was conducted to evaluate the effect of either individual or combined wheat bran(WB) replacement with Azolla pinnata supplemented with Digestin^(TM) in the diet of freshwater prawn, Macrobrachium rosenbergii Postlarvae(PL) on growth performance, nutrient utilization, chemical body composition and survival(%). Experimental diets were a wheat bran-soybean based diet with no Azolla and Digestin^(TM)(control, T_1), and diets containing 17% Azolla supplemented with Digestin^(TM) 0%(T_2), 1%(T_3), 2%(T_4) and 3%(T 5). Each experimental diet was allocated into three tanks(6 m^3/tank) fed for 12 wks. Each tank was subdivided into three equal pens by nets(2 m^3) and stoked with 84 PL/m^2. The experimental diets were readily consumed by prawns PLs where both high growth and good feed efficiency were achieved for all diets. The results showed that the diets containing A. pinnata supplemented with Digestin? at the level up to 3% have the higher growth and better nutrient utilization than the control diet. No differences were observed for moisture and protein content among the experimental diets. However, the highest protein content was observed on prawns fed on diets T_1 and T 5 respectively, while the lowest value was recorded for T_4 diet. The results also show that prawn PLs fed the diets contain A. pinnata and supplemented with Digestin^(TM) recorded the highest values of body lipid content compared to the control diet. Feed efficiency and economic conversion rate(ECR) values show that economic performance and the cost-effectiveness of the A. pinnata supplemented with up to 3% Digestin^(TM) recorded the highest net return, and therefore it is recommended for prawn, M. rosenbergii PL's. These results are clearly indicating that A. pinnata have a good potential for use in prawn diets at reasonable levels than other conventional diets.

关键词： Azolla meal enzymes growth performance economic analysis feed efficiency

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