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1.
Int J Food Microbiol ; 411: 110549, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38157636

RESUMO

Bouhezza is a traditional Algerian cheese produced and ripened in goatskin bags called Djeld. The aim of this study was to characterize the microbial ecosystem from Djeld (fresh and dried Djeld for making Bouhezza cheese) and the changes introduced by Lben microflora during its preparation and to identify its role in cheesemaking and its safety. Two replicates of fresh and dried skin bags (FS and DS) were sampled and analyzed before and after contact with Lben. The microbiological results showed no pathogens. Skins observed before the addition of Lben were less populated 2.86 and 3.20 log CFU cm-2 than skins examined after the addition of Lben (approximately 6.0 log CFU cm-2), suggesting a potential role of Lben in releasing some microorganisms into the skin during its time in the Djeld. However, an increase in mesophilic lactic acid bacteria and yeasts was observed in Lben after different periods of interaction with the skin. PCR-TTGE revealed the predominance of lactic acid bacteria (Lactiplantibacillus plantarum, Limosilactobacillus fermentum, Staphylococcus equorum subsp. linens, Lactococcus cremoris, Streptococcus thermophilus) and a few high-GC-content bacteria (Lacticaseibacillus paracasei, Brevibacterium casei). Transfer of several microbial species was observed between the goatskin bag biofilm and Lben during the overnight interaction. Bands corresponding to Lacticaseibacillus paracasei, Brevibacterium casei, and Lactobacillus delbrueckii subsp. lactis were detected in the fresh skin profile and in Lben after contact with the fresh skin. Lacticaseibacillus paracasei was found in dried skin and Lben after contact with dry skin. Lactobacillus helveticus and Enterococcus faecalis appeared in the Lben profile and persisted in Lben and the biofilm-covered dry skin after interaction. These results demonstrate an exchange of specific microbial populations between goatskin bag biofilm and Lben during the traditional preparation method, suggesting that the diversity of goatskin biofilm contributes to the microbial diversity of Lben used in the production of Bouhezza cheese.


Assuntos
Queijo , Lactobacillales , Animais , Ecossistema , Lactobacillus , Streptococcus thermophilus , Queijo/microbiologia , Contagem de Colônia Microbiana , Leite/microbiologia , Microbiologia de Alimentos
2.
Acta Trop ; 249: 107040, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37839669

RESUMO

Anaplasma species are obligate intracellular rickettsial pathogens that cause significant diseases in animals and humans. Despite their importance, limited information on Anaplasma infections in Algeria has been published thus far. This study aimed to assess the infection rate, characterize Anaplasma species, and identify associated risk factors in selected sheep farms across Oum El Bouaghi region in Algeria. In 2018, we collected 417 blood samples from sheep (Ovis aries) and performed molecular characterization of Anaplasma species infecting these animals. This characterization involved the use of 16S rRNA, msp2, rpoB, and msp5 genes, which were analyzed through nested PCR, qPCR, cPCR, DNA sequencing, and subsequent phylogenetic analysis. Our findings revealed infection rates of 12.7 % for Anaplasma species detected, with Anaplasma ovis at 10.8 %, Anaplasma marginale at 1.7 %, and Anaplasma platys at 0.2 %. Interestingly, all tested animals were found negative for Anaplasma phagocytophilum. Statistical analyses, including the Chi-square test and Fisher exact test, failed to establish any significant relationships (p > 0.05) between A. ovis and A. platys infections and variables such as age, sex, sampling season, and tick infestation level. However, A. marginale infection exhibited a significant association with age (p < 0.05), with a higher incidence observed in lambs (5.2 %) compared to other age groups. Remarkably, this study represents the first molecular detection of A. platys and A. marginale in Algerian sheep. These findings suggest that Algerian sheep may serve as potential reservoirs for these pathogens. This research contributes valuable insights into the prevalence and characteristics of Anaplasma infections in Algerian sheep populations, emphasizing the need for further investigation and enhanced surveillance to better understand and manage these diseases.


Assuntos
Anaplasma marginale , Anaplasmose , Humanos , Animais , Ovinos , Anaplasma marginale/genética , Anaplasmose/epidemiologia , RNA Ribossômico 16S/genética , Argélia/epidemiologia , Filogenia
3.
Heliyon ; 9(12): e22909, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38125537

RESUMO

The use of biochar has recently garnered significant attention as an agricultural management technique highly endorsed by the scientific community. Biochar, owing to its high carbon content, contributes to increased organic matter storage in the soil, consequently enhancing crop growth. This study aimed to elucidate changes in physicochemical soil fertility and durum wheat (Triticum durum) var. Vitron production under the influence of three biochar doses (0 g/kg, 5 g/kg, and 15 g/kg of soil) in combination with varying levels of drought stress (100 %, 80 %, 40 %, and 20 % of field capacity 'FC'). Notably, we observed a substantial increase in all physicochemical soil parameters, except for active calcium carbonate equivalent (ACCE), which displayed lower values (8.78 ± 1.43 %) in soils treated with biochar compared to control soil (15.69 ± 4.03 %). The biochar dose of 5 g/kg yielded the highest moisture content (8.81 %) and pH value (7.83). However, the highest organic matter content (4.89 ± 0.17 %) and total calcium carbonate equivalent 'TCCE' (3.67 ± 0.48 %) were observed with the dose 15 g/kg. Nevertheless, regarding plant growth, no improvements were observed in terms of height and above-ground biomass (AGB). Conversely, leaf surface area exhibited significant changes with biochar application, along with an increase in chlorophyll pigment content. On the other hand, drought stress significantly hindered plant height, AGB, and leaf water reserves, resulting in values of 13.48 ± 1.60 cm, 1.57 ± 0.31g/plant, and 41.79 ± 1.67 %, respectively. The interaction between biochar and water stress appeared to mitigate and limit the impact of stress. Notably, an enhancement in organic matter storage and soil water reserves was observed. For example, the moisture content in the control soil was 6.95 %, while it increased to 12.76 % for 15g biochar/kg and 80 % FC. A similar trend was observed for organic matter, TCCE, and electrical conductivity. This effect positively influenced chlorophyll a and b content, as well as leaf water content. However, when stress was combined with biochar amendment, plant height and AGB decreased. The addition of biochar improved soil fertility and physiological parameters of wheat plants. Nevertheless, when combined with water stress, especially in cases of reduced water reserves, productivity did not witness any significant improvements.

4.
Water Sci Technol ; 88(9): 2473-2489, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37966196

RESUMO

This study was conducted in two natural meadows: first, soils were irrigated with raw wastewater (SIRWW) and in the second, soils were irrigated with treated wastewater (SITWW). Earthworms were sampled in eight soil blocks spaced 10 m apart at each site. Earthworm community was characterized and compared using density, biomass, composition, structure, species richness, and diversity parameters. At both meadows, 459 earthworm individuals from two families and seven species were collected. The highest earthworm density and species richness were recorded at SIRWW. Nicodrilus caligenus was the most abundant species. Most of earthworm community parameters decreased significantly at SITWW. Only two species (N. caligenus and Octodrilus complanatus) were common between the two grasslands. Among the seven species identified at both meadows, four (Allolobophora longa, Eisenia foetida, Allolobophora rosea, Allolobophora chlorotica) were exclusively present in SIRWW, whereas a single species (Amynthas sp.) was characterized in SITWW. Three ecological earthworm groups (epigeic, endogeic, and anectic) were represented in SIRWW, with the dominance of endogeics. Further studies are needed to quantify pollution in this soils and the accumulation of pollutant load in earthworms. It is also important to highlight the relationship between the abundance and diversity of earthworms in these two ecosystems with soil biological activity.


Assuntos
Oligoquetos , Poluentes do Solo , Humanos , Animais , Solo/química , Águas Residuárias , Ecossistema , Biomassa , Poluentes do Solo/análise
5.
Heliyon ; 9(4): e14615, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37025866

RESUMO

With soil fertility loss reached a critical state in arid and semi-arid regions, farmers are constrained to use mineral fertilizers, which are costly, non-eco-friendly and less effective in improving soil fertility than organic fertilizers such as dewatered sewage sludge (SS) and poultry manure (PM). In this regard, the current study aimed to highlight through experiments the positive effect of SS and PM applications on soil fertility and durum wheat growth. It targeted to demonstrate the safe and wise use of organic fertilization while assessing heavy metals in both soil and plant. The experiment was carried out in two batches of thirty-two pots, one for each treatment (SS and PM), in addition to the control with no fertilization. SS and PM were applied separately in three doses (D1 = 50 g, D2 = 100 g, and D3 = 200 g DM fertilizer/pot). The applications of both SS and PM induced a significant increase in plant-available phosphorus, organic matter, nitrates, moisture and electrical conductivity in soil, where these improvements were higher in PM compared to SS treatment. A significant accumulation of proline associated with an increase in biomass that were both proportional with fertilizer dose levels. Our findings revealed a loss in relative water content and leaf area of the plant. Correlations showed several significant relationships between soil parameters studied. The dose D2 of each fertilizer was the most efficient to improving both soil properties and plant components. Plant zinc concentration increased significantly with increase in soil zinc in PM amendments, however it decreased in SS. These relationships were not significant in copper for the two fertilizers. Both SS and PM improved soil fertility and plant growth compared to the control, thus this practice is a promising solution to tackle soil fertility loss and low production in drylands.

6.
Sci Rep ; 13(1): 1991, 2023 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-36737632

RESUMO

Quinoa is an important Andean crop that can play a strategic role in the development of degraded lands in hot arid regions due to its high nutritional value, genetic diversity and its high adaptability to stressful environments. The aim of this work was to evaluate the agronomic performance (growth development, grain yield and grain quality characteristics) of seven quinoa genotypes (Giza1, Sajama, Santa Maria, Q102, Q29, Q27 and Q18) cultivated under open field conditions in the Sahara Desert of Algeria. Using randomized complete block design (4 blocks), field trials were conducted during two cropping seasons (2017-2018 and 2018-2019) from November to April. The measured parameters included: plant height, number of panicles per plant, 1000-grain weight (TGW), grain yield (GYd), grain protein content (GPt), grain saponin content (GSC), and maturity indicators. The genotype effect was statistically the main source of variation in most parameters investigated as compared to the effect of cropping year. The Q102 genotype produced the highest GYd (2.87 t/ha) and GPt (16.7 g/100 g DM); and it required medium period (149 days) to reach harvest maturity as compared to other genotypes. The genotype Giza1 showed the lowest GYd and also low values for most of traits measured. However, it had the shortest harvest maturity (139 days) and the lowest GSC (0.62 g/100 g DM). The variety Santa Maria recorded the highest TGW (2.68 g), but it took 164 days to reach harvest maturity and it had high GSC (1.92 g/100 g DM). Though the best yield and grain quality characteristics were not reunited in single genotype, our findings showed that quinoa has multi-benefit potentials as a new crop for the arid agriculture in particular in hot-arid regions of North Africa.


Assuntos
Chenopodium quinoa , Chenopodium quinoa/metabolismo , Grão Comestível/genética , Genótipo , Fenótipo , Estações do Ano
7.
Acta Trop ; 234: 106588, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35803337

RESUMO

Culicoides biting midges are well known biological vectors of several arboviruses causing more than 100 veterinary and medical diseases worldwide. In Algeria, bluetongue virus, which is transmitted by Culicoides midges, is responsible for one of the most critical insect-borne diseases of sheep. For example, this disease caused clinically severe morbidity of about 2,661 confirmed cases out of 21,175 susceptible sheep in Algeria. This study compared the abundance, richness, and diversity of Culicoides species in rural and suburban environments of semi-arid regions in North Africa. It examined the potential influence of the bio-climatic factors on the variation of population sizes and the elevation distribution of biting midges. Specimen collection was carried out from June to September during two successive years (2018 and 2019) using CDC light traps installed at 15 sites in different environments. Culicoides specimens were dissected, slide-mounted, and morphologically identified using the interactive identification key IIKC and various standard morphological criteria. A total of 1,046 Culicoides specimens (1,024 females and 22 males) were trapped and classified into 22 species, belonged to nine distinct subgenera. Two new species records for Algeria and even North Africa are reported: Culicoides albicans (Winnertz, 1852) and Culicoides nubeculosus (Meigen, 1830). Culicoides newsteadi Austen, 1921 (51.6%) was the dominant species, and it was followed by Culicoides punctatus (Meigen, 1804) (16.3%) and Culicoides odiatus Austen, 1921 (11.5%). These three species, comprising 80% of the collected Culicoides, were the most abundant both outside and inside livestock stables in rural and suburban environments. Species diversity was similar in the two settings, with a slight increase in suburban environments. None of the Culicoides species encountered correlated significantly with the climatic factors (mean temperature, precipitation, and relative humidity). Elevation was the most determinant environmental parameter that affected the abundance and distribution of Culicoides midges in the semi-arid and sub-humid areas studied. The maximum distribution of Culicoides species was detected at mid elevations (400‒800 m). Using a modeling approach, we explored for the first time the variation of composition and diversity in Culicoides communities within different climatic regions, environments and livestock settings in Algeria. This survey deepens our understanding of the relationships among environmental factors, abundance, diversity, and geographic distribution of Culicoides. This is a crucial step to assess the epidemiological situation of the diseases transmitted by these biting midges and to allow mitigation of the associated risks.


Assuntos
Vírus Bluetongue , Ceratopogonidae , Argélia , Animais , Feminino , Insetos Vetores , Gado , Masculino , Ovinos
8.
Chemosphere ; 282: 131122, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34119732

RESUMO

The fertilization using sewage sludge (SS) and/or SS-derived products have been extensively studied and known to increase crop yield as soil nutrients and plant growth are improved. This study aimed to evaluate two SS application methods (i.e. mulching and mixing with the soil) on soil fertility parameters and the productivity of cereal crops. It compared the effect of SS fertilization methods on changes in soil physicochemical parameters in order to highlight the application mode which gives the best agronomic values and sustains soil productivity. Foliar surface, grain starch content and grain yield of durum wheat (Triticum durum) were determined in plants grown in plastic planters for different fertilization treatments (SS-mulched, SS-mixed, urea, and unfertilized). Each SS treatment was applied in three levels (SS1 = 1% w/w ratio, SS2 = 4%, SS3 = 8.3%). The application of SS improved all soil properties compared to the control and urea, with the SS mulching treatment was the best. The significant improvement of soil fertility was confirmed by soil C:P ratio which indicated a good soil mineralization status, in particular under the screen formed by mulching that helped to conserve high soil moisture for optimizing plant growth. Soil calcium accumulated in greater amount in biosolid-soil mixtures than in SS-mulched soils. Regardless of SS doses, the highest crop grain yields were obtained with the SS mulch treatments. Mulching SS, compared to SS-mixed soils, brings better results in terms of improving soil fertility and yielding high productions. The applicable of this method is also easy in the field and/or large-scale cultures.


Assuntos
Poluentes do Solo , Solo , Agricultura , Biossólidos , Fertilizantes/análise , Esgotos , Poluentes do Solo/análise , Triticum
9.
Chemosphere ; 219: 76-88, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30529856

RESUMO

Beni Haroun Dam is a vital water resource for both potable water and irrigation in eastern Algeria. This study assessed water quality at the dam and investigated the impacts of this water on some soil characteristics of irrigated lands. The physicochemical parameters of the water were measured monthly at eight sites and related to soil characteristics sampled from six irrigated areas, which were compared to non-irrigated soils. The chemical facies of the water were chloride sulfate and calcium magnesium. The water had low levels of cadmium (8.9 µg/L) and lead (4.55 µg/L), excessive contents of chloride and bicarbonate, while pH ranged between 6.5 and 8.4. High levels of electrical conductivity were measured in 39% of samples that exceeded standard for irrigation use. Richard diagram identified four classes of water: (i) C3S1 with 61.5% of samples having moderate or poor quality, (ii) C4S1 (30.2%) having poor or bad quality, (iii) C4S2 (5.2%) having very bad quality, and (iv) C5S3 (3.1%) determined unsuitable for irrigation. A Wilcox diagram revealed that 58% of samples had good quality while 42% were inappropriate for irrigation. Soil pH, EC and OM increased in irrigated soils, particularly in the surface horizon, compared to the control sites; whereas total CaCO3 decreased at all soil depths measured. High levels of bioavailable lead (35.82 µg/g) and cadmium (0.22 µg/g) were recorded in the surface soil. The study suggests that adequate protection measures with appropriate guidelines for various water and soil parameters are needed to minimize the detrimental effects of irrigation water on agricultural lands.


Assuntos
Irrigação Agrícola , Água Potável , Água Doce/química , Solo/química , Qualidade da Água , Argélia , Água Potável/química , Monitoramento Ambiental , Poluentes Químicos da Água/análise
10.
Iran J Public Health ; 47(8): 1119-1127, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30186783

RESUMO

BACKGROUND: Diabetes is now a real global disease in particular due to various health problems associated with it. This study aimed to establish the relationship between diabetes and some biochemical parameters to assess the metabolic profile of an adult diabetic population in the region of Tebessa (Northeast Algeria). METHODS: A cross-sectional survey was conducted at the Public Health Facility and the House of Diabetics in Tebessa between Feb 2013 and Apr 2013. The study included 200 subjects (100 controls and 100 diabetics) aged 18-85 yr, chosen completely randomly. RESULTS: Type 2 diabetes mellitus (37%) was significantly more frequent than type 1 diabetes mellitus (13%). It was significantly more frequent in women than in men. The diabetes was highly correlated with the age and body mass index of patients. Moreover, the two types of diabetics have significantly more diseases and metabolic disorders compared to control subjects. CONCLUSION: Diabetics especially type 2 has significantly higher metabolic disorders and associated diseases than type 1 and control subjects.

11.
Sci Total Environ ; 639: 156-174, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-29783116

RESUMO

Heavy metals are a serious hazard for aquatic ecosystems and human health. They negatively affect aquatic life functioning through accumulation resulting physiological/growth disturbances in aquatic lifeforms. This survey focused on the assessment of heavy metal pollution in the Gulf of Annaba (northeastern Algeria), the largest and most diversified industrial hub in Africa, using a multi-compartment approach (water-sediment-biota). The study aims to characterize the spatiotemporal variation of trace metal (TM) contamination and its effects on the growth of the Flathead grey mullet (Mugil cephalus). It reviewed TM concentrations in upper sediments and organs of M. cephalus from various hydrosystems worldwide. Five sites distributed along the Gulf were sampled to determine water physicochemical parameters as well as the contamination of surficial sediments and muscles of M. cephalus by zinc, copper, lead, cadmium and mercury. The spatiotemporal variations of the measured parameters were tested and discussed following the synergetic effects of water, sediment and muscle variables on fish biometrics. The sediments at the Port, Joinoville and Sidi-Salem sites were classified as heavily polluted by lead, copper, zinc and cadmium, whereas only at the Port by mercury. Muscular lead concentrations exceeded international standard values in Joinoville and Port, and zinc in Port. The increase of water dissolved oxygen induced a significant decrease in sediment TM. The increase of sediment TM caused a significant increase in muscle TM levels. The S-shaped logistic models indicated that muscle contaminations reached a saturation plateaus following the current sediment pollution. TM concentrations in fish muscles negatively affected fish weight, but only copper and cadmium significantly influenced fish length. The consumption of fish from the Port, Joinoville and Sidi-Salem can be dangerous because concentrations of lead, zinc and cadmium exceeded the international standards. This study validates the effectiveness of biomonitoring using M. cephalus as bioindicator in polluted coasts.


Assuntos
Monitoramento Ambiental , Metais Pesados/metabolismo , Smegmamorpha/fisiologia , Poluentes Químicos da Água/metabolismo , África , Argélia , Animais , Sedimentos Geológicos/química , Humanos , Mar Mediterrâneo
12.
Environ Monit Assess ; 189(6): 265, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28493182

RESUMO

Industrialization and urbanization are the main sources of pollutions worldwide and particularly in developing countries. This study aims the determination of anthropogenic inputs with trace metals in aquatic ecosystems at the Plain of Annaba (NE Algeria), which is known as one of the largest industrial areas in Africa. Samples of surface waters and upper sediments were conducted in six stations: four in Meboudja wadi and two in Seybouse wadi. Contents of iron, copper, chromium, nickel, zinc, and manganese were measured by atomic absorption spectrophotometry, whereas Cd and Pb were determined using electrothermal atomic absorption spectrometry. Measurements of Hg were carried out using atomic fluorescence. Spatiotemporal variations of metal concentrations were tested using generalized linear models (GLM), whereas the influence of water pollution on sediment contamination was tested with generalized additive models (GAMs). Metal contents measured in surface water and sediments varied differently from upstream to downstream of the study wadis and between seasons. The results showed that the surface water was polluted with high levels of iron, nickel, chromium, lead, and cadmium. Values of the contamination index revealed that the surface sediments were contaminated by iron, chromium, lead, and cadmium. The GAMs indicated that water-phase metal concentrations had no significant effects on trace metal concentrations in the sediment. This suggests that seasonal metal concentrations in water phase, which are measured during the study period (2012) and are time-dependent, contribute increasingly and gradually over time-not immediately-to the accumulation of metals into the sediments. Therefore, the long-term accumulation of metals in the sediments resulted from the continuous discharges of metals in the water phase. The anthropogenic impacts are marked by high contaminations of Meboudja wadi particularly in downstream areas of the steel factory and the nearby industrial areas. The direct industrial discharges into the water and atmosphere (iron, lead, cadmium) as well as urban disposals and agricultural activities are at the origin of these contaminations.


Assuntos
Monitoramento Ambiental , Metais/análise , Modelos Químicos , Poluentes Químicos da Água/análise , África , África do Norte , Argélia , Cádmio/análise , Cromo/análise , Cobre/análise , Sedimentos Geológicos/química , Ferro/análise , Manganês/análise , Níquel/análise , Estações do Ano , Espectrofotometria Atômica , Urbanização , Zinco/análise
13.
Sci Total Environ ; 583: 176-189, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28094046

RESUMO

This study aims to determine the spatiotemporal dynamics of root colonization and spore density of arbuscular mycorrhizal fungi (AMF) in the rhizosphere of olive trees (Olea europaea) with different plantation ages and under different climatic areas in Algeria. Soil and root samples were seasonally collected from three olive plantations of different ages. Other samples were carried out in productive olive orchards cultivated under a climatic gradient (desertic, semi-arid, subhumid, and humid). The olive varieties analysed in this study were Blanquette, Rougette, Chemlel and the wild-olive. Spore density, mycorrhization intensity (M%), spore diversity and the most probable number (MPN) were determined. Both the intensity of mycorrhizal colonization and spore density increased with the increase of seasonal precipitation and decreased with the increase of air temperature regardless of the climatic region or olive variety. The variety Rougette had the highest mycorrhizal levels in all plantation ages and climates. Spore community was composed of the genera Rhizophagus, Funneliformis, Glomus, Septoglomus, Gigaspora, Scutellospora and Entrophospora. The genus Glomus, with four species, predominated in all climate regions. Spores of Gigaspora sp. and Scutellospora sp. were the most abundant in desertic plantations. Statistical models indicated a positive relationship between spore density and M% during spring and winter in young seedlings and old plantations. A significant positive relationship was found between MPN and spore density under different climates. For a mycotrophic species, the rhizosphere of olive trees proved to be poor in mycorrhiza in terms of mycorrhizal colonization and numbers of the infective AMF propagules.


Assuntos
Monitoramento Ambiental , Micorrizas/classificação , Rizosfera , Microbiologia do Solo , África do Norte , Argélia , Biodiversidade , Glomeromycota , Micorrizas/crescimento & desenvolvimento , Olea , Raízes de Plantas/microbiologia , Estações do Ano , Solo , Esporos Fúngicos
14.
Sci Total Environ ; 575: 660-671, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27639781

RESUMO

This study aims to characterize soil properties and to investigate how these parameters, including soil salinity, are related to zonation and distributional patterns of halophytic plants occurring at edges of the Djendli Sabkha (northeastern Algeria). Soil samples were collected from four stations at Sabkha edges with seven samples for each station. Physicochemical soil parameters were analysed in each vegetation belt of halophytes. Relationships between soil traits were tested to determine spatial variation and their effects on vegetation cover of the principal halophyte species. The influence of pedological factors on the distribution and establishment of halophytes was considered using a redundancy analysis (RDA) and generalized linear models. Positive correlations were found between organic matter, carbon and nitrogen which were negatively correlated with electrical conductivity (EC), pH, gypsum, Na+ and Cl- concentrations. Sharp limits were found between halophyte communities even though there is a gradual change in the physicochemical environment along the gradient centre-to-edge of the Sabkha. RDA showed that edaphic variables that best explained the data were EC, pH, organic matter (OM), carbon and nitrogen contents, Na+ and Cl- concentrations. Sarcocornia fruticosa grew under higher soil salinity (EC=7.2-13.8dS/m) compared to Suaeda fruticosa and Suaeda vermiculata that afford moderate soil salinity, than Atriplex halimus established in soils with low EC values (5.5-7.3dS/m) but with high values of OM, carbon and nitrogen contents and low values of Na+, Cl- and pH. Sarcocornia fruticosa grew in soils characterized with high pH, Na+, Cl- values but relatively low in OM, carbon and nitrogen contents.

15.
Int J Biometeorol ; 61(3): 549-564, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27582284

RESUMO

Assessing diet composition of White Storks (Ciconia ciconia) breeding under North African conditions provides key information to understanding its trophic niche for conservation purpose. Since, climate controls productivities of foraging habitats and thus food availability for predators, this study examines how Storks' diet parameters varied following a climate gradient along with rural-to-urban landscapes in north-eastern Algeria. Feeding strategies to cope with severe conditions were discussed in light of climate aridity and urbanization and how these influence reproduction, population dynamics and distribution. While invertebrate prey accounted for 94 % of ingested individuals, the biomass intake was dominated by chicken remains scavenged from rubbish dumps (67 %) and small mammals (14 %). Generalized linear models revealed that prey numbers varied significantly between climatic regions and landscapes types, but no significant differences were observed for other dietary parameters, including prey biomass. The study showed high dietary similarity between study climates and landscapes, mainly among rural and urban colonies located in semi-arid and sub-humid areas, which differed from those in suburban and arid climate. Rarefaction and extrapolation curves indicated that prey species richness in White Stork diets was expected to be higher in urban colonies located in sub-humid climate. Despite low prey species diversity in arid regions, the White Stork demonstrates a broad trophic niche, which could be due to supplementary feeding from human refuse. This study suggests that regardless of the climate or landscape, White Storks ensure a constant food intake, despite prey biomass fluctuations, by adapting their diet. Foraging in diverse habitats, including trash dumps, ensures a sufficiently balanced diet to meet nutritional requirements.


Assuntos
Aves , Clima , Dieta , África do Norte , Animais , Cidades , Ecossistema , Comportamento Alimentar , Urbanização , Instalações de Eliminação de Resíduos
16.
J Arthropod Borne Dis ; 10(1): 24-38, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27047969

RESUMO

BACKGROUND: Algeria is among the most affected Mediterranean countries by leishmaniasis due to its large geographic extent and climatic diversity. The current study aimed to determine the ecological status (composition and diversity) of phlebotomine sandfly populations in the region of Oum El Bouaghi (Northeast Algeria). METHODS: An entomological survey was conducted during the period May-October 2010 in rural communities of Oum El Bouaghi. Catches of sandflies were carried out using sticky traps in both domestic and peri-domestic environments of 16 sites located beneath two bioclimatic areas, sub-humid and semi-arid. Most of these sites have visceral and/or cutaneous leishmaniasis cases. RESULTS: A total of 1,363 sandflies were captured and identified. They belong to two genera, Phlebotomus and Sergentomyia, and five species. The species Phlebotomus perniciosus, P. perfiliewi and Sergentomyia minuta were constants. Phlebotomus longicuspis was common and P. papatasi was accidental in the study sites. P. perniciosus and P. perfiliewi are the two possible species that contribute in leishmaniasis transmission across the study area due to their high densities (96 and 49 specimens/m(2)/night, respectively); these two species dominate other species in all study sites. CONCLUSION: Findings emphasize the key-role played by P. perniciosus, P. perfiliewi and S. minuta in outlining site similarities based on sandfly densities. The study confirms that the more susceptible sites to leishmaniasis, which hold high densities of these sandflies, were located south of the study area under a semi-arid climate.

17.
Iran J Public Health ; 45(12): 1636-1644, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28053930

RESUMO

BACKGROUND: Diabetes mellitus is a serious public health problem worldwide and particularly in developing countries. In Algeria, this metabolic disorder occurs with a wide variety or atypical forms that linked to multiple risk factors including local habits and traditions. This study aimed to determine the impact of risk factors (metabolic syndrome, social, cultural, physical activity, family history and the treatment used) on the incidence of diabetes. METHODS: This cross-sectional study was conducted in 2013 on a random sample from a resident population in Tebessa, Northeast Algeria, which underwent a significant expanding of diabetes prevalence conditioned by profound socioeconomic changes. The survey included 200 subjects, randomly selected; with 100 controls and 100 diabetic patients, (26 diabetic subjects with type 1 diabetes mellitus 'T1DM' and 74 subjects with type two diabetes mellitus 'T2DM'). RESULTS: Diabetic subjects were significantly affected by all these risk factors, including metabolic syndrome that was higher in women. The most common treatment among surveyed T1DM subjects was insulin, whereas T2DM patients used metformin. In addition, the duration from T1DM onset in the surveyed subjects is older than T2DM onset. The incidence of diabetes is significantly in close relationship between the majorities of these factors of risk. CONCLUSION: Subjects with a high socioeconomic status can afford a healthier way of life to avoid the risk of developing diabetes compared to subjects with lower social level.

18.
Front Microbiol ; 6: 1239, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26594206

RESUMO

BACKGROUND: Honey has multiple therapeutic properties due to its composition with diverse components. OBJECTIVES: This study aims to investigate the antimicrobial efficacy of Saharan honeys against bacterial pathogens, the variation of honey floral origins, and its physicochemical characteristics. MATERIALS AND METHODS: The antimicrobial activity of 32 samples of honey collected from the Algerian Sahara Desert was tested on four bacteria; Bacillus subtilis, Clostridium perfringens, Escherichia coli, and Staphylococcus aureus. The botanical origin of honeys and their physicochemical properties were determined and their combined antibacterial effects were modeled using a generalized linear mixed model (GLMM). RESULTS: Out of the 32 study samples, 14 were monofloral and 18 were multifloral. The pollen density was on average 7.86 × 10(6) grains/10 g of honey, water content was 14.6%, electrical conductivity (EC) was 0.5 µS/cm, pH was 4.38 ± 0 50, hydroxymethylfurfural (HMF) content was 82 mg/kg of honey, total sugars = 83%, reducing sugars = 71%, and the concentration of proline = 525.5 ± 550.2 mg/kg of honey. GLMM revealed that the antibacterial effect of honey varied significantly between bacteria and floral origins. This effect increased with increasing of water content and reducing sugars in honey, but it significantly decreased with increase of honey EC. E. coli was the most sensitive species with an inhibition zone of 10.1 ± 4.7 mm, while C. perfringens was the less sensitive. Honeys dominated by pollen of Fabaceae sp. were most effective with an overall antimicrobial activity equals to 13.5 ± 4.7 mm. CONCLUSION: Saharan honeys, of certain botanical origins, have physicochemical and pollinic characteristics with relevant potential for antibacterial purposes. This encourages a more comprehensive characterization of honeys with in vivo and in vitro investigations.

19.
EXCLI J ; 14: 320-34, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26417365

RESUMO

In arid and semi-arid areas, low soil fertility and water deficit considerably limit crop production. The use of sewage sludge as an organic amendment could contribute to the improvement of soil fertility and hence the agronomic production. The study aims to highlight the behaviour of durum wheat to the application of sewage sludge associated with water stress. The assessment focused on morphophysiological parameters of the wheat plant and yield. Under greenhouse conditions, the variety Mohamed Ben Bachir was treated by four water stress levels (100 %, 80 %, 50 % and 30 %). Each stress level comprised five fertilizer treatments: 20, 50 and 100 t/ha of dry sludge, 35 kg/ha of urea, and a control with no fertilization. Results revealed a significant loss in water content and chlorophyll a in leaves. Water stress negatively affected the development of wheat plants by reducing significantly seed yield, leaf area and biomass produced. Plant's responses to water stress manifested by an accumulation of proline and a decrease in total phosphorus. However, the increasing doses of sewage sludge limited the effect of water stress. Our findings showed an increase in the amount of chlorophyll pigments, leaf area, total phosphorus, biomass and yield. In addition, excessive accumulation of proline (1.11 ± 1.03 µg/g DM) was recorded as a result of the high concentration of sludge (100 t/ha DM). The application of sewage sludge is beneficial for the wheat crop, but the high accumulation of proline in plants treated with high dose of sludge suggests to properly consider this fact. The application of sludge should be used with caution in soils where water is limited. Because the combined effect of these two factors could result in a fatal osmotic stress to crop development.

20.
PeerJ ; 3: e860, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25825682

RESUMO

The current study highlights some knowledge on the diversity and structure of insect communities and trophic groups living in Sabkha Djendli (semi-arid area of Northeastern Algeria). The entomofauna was monthly sampled from March to November 2006 using pitfall traps at eight sites located at the vicinity of the Sabkha. Structural and diversity parameters (species richness, Shannon index, evenness) were measured for both insect orders and trophic guilds. The canonical correspondence analysis (CCA) was applied to determine how vegetation parameters (species richness and cover) influence spatial and seasonal fluctuations of insect assemblages. The catches totalled 434 insect individuals classified into 75 species, 62 genera, 31 families and 7 orders, of which Coleoptera and Hymenoptera were the most abundant and constant over seasons and study stations. Spring and autumn presented the highest values of diversity parameters. Individual-based Chao-1 species richness estimator indicated 126 species for the total individuals captured in the Sabkha. Based on catch abundances, the structure of functional trophic groups was predators (37.3%), saprophages (26.7%), phytophages (20.5%), polyphages (10.8%), coprophages (4.6%); whereas in terms of numbers of species, they can be classified as phytophages (40%), predators (25.3%), polyphages (13.3%), saprophages (12%), coprophages (9.3%). The CCA demonstrated that phytophages and saprophages as well as Coleoptera and Orthoptera were positively correlated with the two parameters of vegetation, especially in spring and summer. While the abundance of coprophages was positively correlated with species richness of plants, polyphage density was positively associated with vegetation cover. The insect community showed high taxonomic and functional diversity that is closely related to diversity and vegetation cover in different stations of the wetland and seasons.

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