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1.
Hamid Mahyou Bernard Tychon Marie Lang Riad Balaghi 《African Journal of Range and Forage Science》2018,35(1):1-12
The assessment of rangeland productivity in semi-extensively grazed arid rangelands is a prerequisite for livestock management in relation to sustainable use of pastoral resources. The objective of this study was to assess rangeland productivity based on normalised difference vegetation index (NDVI) images. Data on phytomass were measured on 61 field samples in arid rangelands of Morocco, covering various rangeland categories during autumn (November) and spring (April), i.e. when phytomass is at low and high levels, respectively, for two consecutive years (2008 and 2009). Dekadal EROS Moderate Resolution Imaging Spectroradiometer (eMODIS) NDVI data were linearly regressed to field measurements for these four periods. Results show that phytomass values were correlated with NDVI during spring, with R2 and RMSE values of 0.82 and 0.3 t ha?1, respectively. This study indicates there is a high potential for operational use of remotely sensed data to estimate rangeland phytomass of semi-extensively grazed rangelands. 相似文献
2.
Hamid Mahyou Bernard Tychon Riad Balaghi Mounir Louhaichi Jamal Mimouni 《Land Degradation \u0026amp; Development》2016,27(6):1574-1585
Rangelands cover about 82% of the arid area of Morocco. It is generally acknowledged that these areas are threatened by desertification. Monitoring desertification requires accurate knowledge about the current status of rangeland degradation. Remote sensing is widely used to assess changes in land cover, but its use in arid rangelands has limitations because of spectral confusion among various types of land cover. The objective of this study was to assess the severity and spatial extent of rangeland degradation in the high plateaus of eastern Morocco, using a knowledge‐based approach combining remote sensing and ancillary data. This approach relies on analyzing datasets derived from Landsat TM satellite imagery, lithology, bioclimatic data and field measurements. The level of rangeland degradation was assessed using indicators such as vegetation parameters, grazing levels and cultivation intensity, which provided a high level of accuracy for mapping and monitoring the degradation of the arid rangelands. The results showed that the total area of degraded rangeland in the high plateaus of eastern Morocco is about 17,417 km2, accounting for 48% in the studied area. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
3.
Eldessouki Elsayed A. A. Diab Amany M. Selema Talal A. M. Abo Sabry Nader M. Abotaleb Mahmoud M. Khalil Riad H. El-Sabbagh Nasser Younis Nehal A. Abdel-Tawwab Mohsen 《Aquaculture International》2022,30(4):1869-1887
Aquaculture International - Astaxanthin (AX) is one of the commonly used feed supplements to enhance the growth performance and provide antioxidant and immune functions of several aquatic animals.... 相似文献
4.
İlhami Gülçin Riad Elias Akçahan Gepdiremen Khalil Taoubi Ekrem Köksal 《Wood Science and Technology》2009,43(3-4):195-212
Recently, a number of studies on health benefits associated with natural compounds have been demonstrated. Phenolics in fruits, vegetables, herbs and spices possess potent antioxidant, anti-inflammatory, antimutagenic and anticarcinogenic activities. The fringe tree (Chionanthus virginicus) is used as a raw material by pharmaceutical industries for the preparation of homeopathy tinctures. The potential antioxidant activities of two secoiridoids from root bark of fringe tree (Chionanthus virginicus L.) were investigated to evaluate their potential value as the natural products for foods or cosmetic applications. In this study, antioxidant activities were measured by 2,2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH·) scavenging, superoxide anion (O 2 ·? ) radical scavenging, total antioxidant activity, reducing activity, hydrogen peroxide (H2O2) scavenging and ferrous metal chelating activity assays. These secoiridoids, as antioxidants neutralized the activities of radicals and inhibited the peroxidation reactions of linoleic acid emulsion. Total antioxidant activity was measured according to ferric thiocyanate method. Butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and trolox, a water-soluble analog of tocopherol, were used as the reference antioxidant compounds. Ligustroside (3.70 × 10?3 M) and oleuropein (3.80 × 10?3 M) showed 71.9, 82.4, 80.7 and 90.4% inhibition on lipid peroxidation of linoleic acid emulsion, at the concentrations of 10 and 20 μg/mL. On the other hand, 20 μg/mL of standard antioxidant such as α-tocopherol (4.64 × 10?3 M), trolox (7.98 × 10?3 M), BHA (10.08 × 10?3 M) and BHT (9.06 × 10?3 M) exhibited 61.5, 29.8, 74.4 and 71.2% inhibition on peroxidation of linoleic acid emulsion, respectively. In addition, ligustroside and oleuropein had effective DPPH·, ABTS·+ and superoxide anion radicals scavenging, hydrogen peroxide scavenging, total reducing power and metal chelating on ferrous ions activities. Also, those various antioxidant activities were compared to BHA and BHT, α-tocopherol and trolox that are references antioxidants. 相似文献
5.
Mohamed Abdel-Rahim Omar Bahattab Fatma Nossir Yahya Al-Awthan Riad H. Khalil Radi Mohamed 《Marine drugs》2021,19(3)
This study was aimed to evaluate the efficiency of Sargassum polycystum and nucleotides- supplemented diets to improve immune response and cold-tolerance of juvenile Litopenaeus vannamei. Four treatments were evaluated: T1, the control, shrimp received only a basal diet; T2, a basal diet with 500 ppm nucleotides; T3, a basal diet with 500 ppm S. polycystum powdered; T4, a basal diet with 500 ppm nucleotides and 500 ppm S. polycystum powdered. Shrimp were fed experimental diets for 56 days. Results revealed shrimp fed T4 diet exhibited the best significant improvement in water quality, survival, growth, and feed utilization indices followed by T2, and T3, while T1 showed the worst values. Additionally, nonspecific immune responses (phagocytosis (%), lysozyme, phenoloxidase, super oxide dismutase (SOD) activity, total nitric oxide) were improved with 1.7–3.2-fold in T4 higher than T1. Histomorphology of hepatopancreas in T4 showed the most increased activation of the hepatic glandular duct system compared with the other treatments. Moreover, nucleotides/seaweed-supplemented diets upregulated relative expression of cMnSOD, Penaeidin4, and heat shock protein70 (HSP70) genes, while translationally controlled tumor protein (TCTP) was downregulated. In conclusion, the synergistic effects of both S. polycystum and nucleotides have many advantages as a growth promoter, immunostimulant, antimicrobial, and cold-tolerant stimulant to L. vannamei. 相似文献
6.
Riad Z. Baalbaki Rami A. Zurayk Mohamed A.M. Adlan Mohan C. Saxena 《Journal of plant nutrition》2013,36(6):805-814
This study aimed at investigating mechanisms of salt tolerance and ionic relations of chickpea (Cicer arietinum L.) cultivars with different nitrogen (N) sources. Two resistant genotypes, ILC‐205 and ILC‐1919, were subjected to four levels of salinity (0.5, 3.0, 6.0, and 9.0 dS m‐1). Nitrogen sources consisted of inoculation with two resistant Rhizobium strains, CP‐29 and CP‐32, mineral N additions, and no N application. Data was collected on root and shoot contents of sodium (Na+) chlorine, (Cl‐,) and potassium (K+), and shoot to root Na+ratio, as well as shoot K+ to Na+ ratio. Salinity affected shoot Na+ and Cl‐contents, but nodulating plants had higher shoot Na+ contents than plants supplied with mineral N. Shoot to root Na+ ratios were lower in the mineral N treatment than in nodulating treatments at 3.0 dS m‐1, indicating that root compartmentalization and shoot exclusion were only possible at low salinities. Potassium levels of nodulating plant shoots were lower than those of non‐nodulating plants only at low salinities. N‐source significantly affected shoot K+/Na+ ratio, with nodulating plants having lower ratios than non‐nodulating plants, indicating that rhizobial infection or nodule formation may lead to salt entry curtailing the selective ability of chickpea roots. 相似文献
7.
Phosphorus (P) is the second major plant nutrient required for plant growth. Different sources of water soluble P have been used to increase growth and yield of legumes. In addition, mycorrhizas have a potential role in increasing soil P supply. A factorial experiment was conducted to evaluate the effect of different phosphorus sources (monoammonium phosphate, monopotassium phosphate, urea phosphate, calcium superphosphate and phosphate rock fortified Bacillus megaterium) and arbuscular mycorrhizal inoculation (with or without) on growth and productivity of snap bean (Phaseolus vulgaris L.) cv. Paulista in plastic bags filled with sandy soil during 2014 and 2015 seasons at the Experimental Research Farm of the Horticulture Department, Faculty of Agriculture, Ain Shams University, Qalyubia Governorate, Egypt. The experiment was laid out in a completely randomized design with three replications. Results revealed that fertilization with monoammonium phosphate (MAP) significantly increased vegetative growth characteristics, yield, and total carbohydrates and protein content in green pods concomitantly with increases in chlorophyll and nutrients content in the leaves. Moreover, arbuscular-mycorrhizal inoculation significantly increased all above mentioned data compared with non-mycorrhizal inoculation. In addition, plants inoculated with arbuscular mycorrhizal and fertilized with MAP showed a synergistic effect. 相似文献
8.
Zurayk Rami Sukkariyah Bishr Baalbaki Riad Abi Ghanem Daad 《Water, air, and soil pollution》2002,137(1-4):355-364
Water, Air, &; Soil Pollution - The ability of scented geraniums (Pelargonium sp. `Frensham’) to uptake cadmium and nickel was assessed undergreenhouse conditions. Plants were grown in an... 相似文献
9.
The cytotoxicity of extracts obtained from plants occurring in the Amazon and Atlantic rain forests against NCI-H460, KM-12, SF-268 and RPMI-8226 cancer cell lines was investigated. Expressive activity was observed in the extracts of Toulicia cf. pulvinata, Ampirrhox sp., Macoubea sprucei, Calophyllum brasiliense, Vismia guianensis, Caryocar microcarpum, Xylopia aromatica and Distictella magnoliifolia. 相似文献
10.
Aflatoxicosis, toxicity of aflatoxin, is of great concern in aquaculture. This study was conducted to assess the efficacies of three adsorbents, a hydrated sodium calcium aluminosilicates (HSCAS), Saccharomyces cerevisiae (S.C.) and an esterified glucomannan (EGM), against feed contaminated with contained 200 μg/kg (ppb) aflatoxin B1 (AFB1). A total of 240 Nile tilapia fingerlings, Oreochromis niloticus (15 ± 2 g), were randomly divided into eight experimental groups (30 fish per group) with three replicates. Group T1 represented the negative control fed on a basal diet, and T2 was the positive control group fed on a basal diet supplemented with 200 ppb AFB1. Groups T3, T4 and T5 were fed the AFB1-contaminated diet (200 ppb) supplemented with 0.5 % HSCAS, 0.25 % S.C or 0.25 % EGM, respectively. Groups T6, T7 and T8 were fed a basal diet supplemented with 0.5 % HSCAS, 0.25 % S.C or 0.25 % EGM, respectively. The reduction in AFB1-bioavailability was judged by toxin residues in fish musculature throughout the study beginning at the second week of exposure. AFB1 reduced the survivability, total weight gain, average daily gain and specific growth rate, evident as early as the second week of exposure. The total erythrocyte count, hemoglobin content and total leukocyte count were significantly decreased after AFB1 exposure for 6, 8 and 10 weeks, respectively. Prolonged administration of AFB1 led to significant increases in serum alanine transaminase, aspartate transaminase and creatinine activity, and produced significant decreases in plasma proteins, including serum globulin. The specific immune response was assessed by an agglutinating antibody titer after immunization of the fish with an Aeromonas hydrophila vaccine. The antibody titer and relative level of protection of fish challenged with Aeromonas hydrophila were reduced throughout the period of examination in AFB1-exposed fish. Supplementation with HSCAS, S.C. or EGM significantly improved growth performance, blood parameters and immune status; in addition, these groups showed decreased AFB1 residues in fish musculature when compared with AFB1-treated fish. HSCAS effectively reduced AFB1 toxicity, whereas S.C. and EGM were less efficacious. 相似文献