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Solute transport and geochemical modeling of the coastal quaternary aquifer, Delta Dahab Basin, South Sinai, Egypt
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作者 Amira Samy Mustafa Eissa +2 位作者 Seham Shahen Moustafa M.Said Rabab M.Abou-shahaba 《Acta Geochimica》 EI CAS CSCD 2024年第1期16-39,共24页
The wadi dahab delta is in a dry, arid coastal zone within Egypt’s south Sinai Peninsula’s eastern portion. The primary water source is the Quaternary coastal alluvial aquifer. The groundwater salinity varies from 8... The wadi dahab delta is in a dry, arid coastal zone within Egypt’s south Sinai Peninsula’s eastern portion. The primary water source is the Quaternary coastal alluvial aquifer. The groundwater salinity varies from 890to 8213 mg/L, with a mean value of 3417 mg/L. The dissolved major ions have been used to calculate the seawater mixing index(SWMI) using a linear equation that discriminates the groundwater mostly affected by water–rock interaction(SWMI 1>) and other samples mixed with Seawater(SWMI < 1). The isotopic composition of groundwater for specifically chosen groundwater samples ranges from-0.645‰ to +5.212‰ for δ^(18)O and from-9.582‰ to + 22.778‰ for δ^(2)H, where the seawater represented by a Red Sea water sample(δ^(18)O + 1.64‰-δ^(2)H + 9.80‰) and reject brine water are considerably enriched the isotopic groundwater values. The geochemical NETPATH model constrained by the dissolved significant ions, isotopes, and the rock aquifer forming minerals as phases indicate the mixing percent with the seawater ranges from 9% to 97% of seawater from 91% to 3% of original recharge water. According to the SEAWAT 3-D flow models, seawater has penetrated the Northeastern Dahab delta aquifer, with the intrusion zone extending1500 m inland. The salt dissolution, upwelling of saline water, recharge from the upstream mountain block, and seawater encroachment are the primary aspects contributing to the deterioration of groundwater quality. These findings may have significance for effective groundwater withdrawal management in arid locations worldwide with similar hydrogeological systems. 展开更多
关键词 Groundwater geochemistry Seawater intrusion Solute transport SEAWAT
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Land desertification and restoration in Middle East and North Africa(MENA) region 被引量:3
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作者 Hassan M.El Shaer 《Research in Cold and Arid Regions》 CSCD 2015年第1期7-15,共9页
The Middle East and North Africa (MENA) region is characterized by high population growth, degraded and fragile nat- ural ecosystems, and a limited amount of arable lands. It is one of the most water-scarce regions ... The Middle East and North Africa (MENA) region is characterized by high population growth, degraded and fragile nat- ural ecosystems, and a limited amount of arable lands. It is one of the most water-scarce regions in the world. The region is heterogeneous in terms of the countries' economies, but because it includes some of the richest and some of the poorest countries in the world, regional average economic performance statistics are misleading. The region is mostly semi-arid and arid, with significant areas of extreme aridity. These areas are further challenged by extreme temperatures, frequent drought, land degradation, and desertification. Recent changes in climate patterns, such as prolonged droughts, record temperatures, and increased rainfall irregularity, intensity and distribution, have all further negatively impacted the natural and agro-ecosystems in the region. Such changes have led to increased vulnerability of the people dependent on such re- sources for their livelihood. This article focuses on the impact of land desertification due to climate changes on the prevailing natural resources, and discusses several approaches for mitigating or alleviating desertification. It is clear that water shortage is a problem in many countries of this predominantly arid region, and is unlikely to be reduced and may be exacerbated by climate change. Proposed adaptation strategies might include more efficient organization of water supplies, treatment, and delivery systems, and increased use of groundwater. It is necessary to develop alternative production and management systems appropriate to the socioeconomic and environmental conditions in order to prevent further degradation of the prevailing agro-ecosystems and sustain the livelihoods of farmers living in marginal conditions. Grasslands, livestock, and water resources are likely to be most vulnerable to climate change in the region because they are located mostly in marginal areas. Changes in cropping practices and improved irrigation practices, and introducing proper livestock-fodder crop production integrated systems, could significantly enhance water use efficiency, eliminate the impact of desertification, and improve local livelihoods. 展开更多
关键词 degradation SALINITY climate changes water resources LIVESTOCK RANGELANDS
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Adaptation to climate change in desertified lands of the marginal regions in Egypt through sustainable crop and livestock diversification systems 被引量:1
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作者 Hassan M.El Shaer 《Research in Cold and Arid Regions》 CSCD 2015年第1期16-22,共7页
Environmental degradation resulting from current climate changes, including prolonged drought, land degradation, desertification, and loss of biodiversity, is presenting enormous challenges to achieve food security an... Environmental degradation resulting from current climate changes, including prolonged drought, land degradation, desertification, and loss of biodiversity, is presenting enormous challenges to achieve food security and eradication of poverty in the marginal regions (about 90% of the total area) of Egypt. In addition to the natural constraints of high temperature, wind erosion, sand dune movement, and recurrent drought, such regions are subjected to improper land and water management. Moreover, there is a lack of knowledge, technologies, and experiences to match with the current severe climatic changes. There is a great need for establishing sustainable integrated ecosystem rehabilitation and management programs to overcome such problems in the marginal areas, particularly in the Sinai Peninsula due to its strategic and social importance. A series of research and development programs have been conducted in 2006 to im- prove the livelihoods of smallholders through enhancing the efficient management and utilization of local resources that can cope with the drastic changes of climate in the Sinai Peninsula. An integrated livestock/salt-tolerant fodder crop system was introduced, in 2010 by the project teamwork of Desert Research center, Egypt, to many smallholders in the South Sinai region, where studies were conducted at both the general research and individual farmer levels. The most important results were: (1) adoption of the most salt-tolerant genotypes of three forage crops: pearl millet (Pennisetum glaucum L.), sorghum (Sorghum bicolor), and Sudan grass (Sorghum sudanense (Piper) Stapf.); two cereal crops (triticale and barley); and two oil crops: safflower (Carthamus tinctorius) and Brassica (Mustard). Alfalfa (Medicago sativa L. and Medicago arborium), cowpeas (Vigna sinensis L.), fodder beets (Beta vulgaris L.), clumping desert bunchgrass (Panicum turgedum), ryegrass (Lolium perenne) Ray grass, forage shrubs (Kochia indica, Atriplex num- mularia, Sesbania sesban L.), and Acacia cyanophila, Leucaena leucocephala, Porsopis cheilanses, and Prosopis jioflora were also evaluated; (2) active participation of farmers in development of management strategies to improve ir- rigation water use efficiency, forage production, and livestock production; and (3) economic evaluation at the farmer level, which showed that feeding livestock salt-tolerant fodders produced an increase of about 60% in milk production and 80% in meat production, and reduced feed costs by about 40%. Accordingly, a 70% increase of family income was achieved. It is concluded that better utilization of fragile ecosystem resources and growing salt-tolerant fodder crops may contribute to the development of marginal areas and enhance the living standards of local people through providing high-quality livestock feed materials and producing economical animal products. 展开更多
关键词 brackish water SALINITY fodder crops LIVESTOCK animal production irrigation EGYPT
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Assessment of the Hydrogeochemical Characteristics of Groundwater Resources at some Wadis in the East of El Minia Governorate,Eastern Desert,Egypt 被引量:1
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作者 Alzahraa Abo HABIBAH Kamal DAHAB +2 位作者 Ashraf SHABANA Samir KAMH Hekmat IBRAHIM 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第3期1082-1097,共16页
The El Minia governorate lies within the Nile Valley,surrounded by calcareous plateaus to the east and west.The present study focuses on the hydrogeochemistry of the Eocene limestone aquifer at some wadis in the east ... The El Minia governorate lies within the Nile Valley,surrounded by calcareous plateaus to the east and west.The present study focuses on the hydrogeochemistry of the Eocene limestone aquifer at some wadis in the east El Minia governorate,Eastern Desert,Egypt.Hydrogeologically,two main aquifers are encountered in the study area,namely the Maghagha marly limestone and the Samalut chalky limestone aquifers.The Maghagha aquifer is composed of alternating layers of marly limestone and shale with thicknesses ranging from 3.49 m to 177.05 m and a groundwater depth ranging from 8.5 m to 59.27 m which reflects low groundwater potentiality.The groundwater salinity representing this aquifer ranges from 603.5 mg/L to 978.5 mg/L,reflecting fresh water type.Samalut aquifer is made up of chalky,cavernous and fractured limestone with thickness ranging from 30 m to 205 m and groundwater depth ranging from 9 m to 86.77 m,which indicates good groundwater potential.The groundwater salinity of the concerned aquifer ranges from 349.7 mg/L to 2043.9 mg/L,reflecting fresh to possibly brackish water types.Groundwater in the study area is of meteoric water origin;recent recharge is mainly controlled through the presence of fractures and their densities.The majority of groundwater samples in the study area are suitable for drinking and irrigation purposes. 展开更多
关键词 GROUNDWATER limestone aquifers El Minia governorate Eastern Desert
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Geochemical Modeling and Statistical Analysis for Groundwater Evolution Assessment in Wadi Qasab, Sohag, Eastern Desert, Egypt
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作者 Ehab Zaghlool 《Journal of Geoscience and Environment Protection》 2020年第9期33-61,共29页
Qasab basin is one of the most promising areas for the sustainable development in the Eastern Desert fringes of the Nile Valley, Egypt. The integration between statistical analysis, stable isotopes as well as geochemi... Qasab basin is one of the most promising areas for the sustainable development in the Eastern Desert fringes of the Nile Valley, Egypt. The integration between statistical analysis, stable isotopes as well as geochemical modeling tools delineated the geochemical possesses affecting groundwater quality and detected the main recharge source in Qasab basin. The most of groundwater samples are brackish (88%), while the minority (12%) of the samples are fresh. The electrical conductivity of groundwater ranged from 1135 to 10,030 μS/cm. The statistical analysis and hydrochemical diagrams suggest that the groundwater quality is mainly controlled by several intermixed processes (rock weathering and agricultural activities). The mineralization of the Pleistocene groundwater is regulated by the rock weathering source, evaporation processes and reverse cation exchange. The isotopic signatures (δ<sup>2</sup>H and δ<sup>18</sup>O) represent two groundwater groups. The first group, is enriched with the isotopic signature of δ<sup>18</sup>O, which ranges from 0.9‰ to 5.5‰. This group is mostly affected by the recent meteoric recharge from the surface water leakage. The second group, is relatively depleted with the isotopic signature of δ<sup>18</sup>O, reflecting a palaeo recharge source of colder climate. The δ<sup>18</sup>O‰ varies from <span style="color:#4F4F4F;font-family:"font-size:14px;white-space:normal;background-color:#FFFFFF;">&#45</span>10.1‰ to <span style="color:#4F4F4F;font-family:"font-size:14px;white-space:normal;background-color:#FFFFFF;">&#45</span>6.4‰, indicating upward leakage of the Nubian sandstone aquifer through deep seated faults. The inverse geochemical model reflects that the salinity source of the groundwater samples is due to the leaching and dissolution processes of carbonate, sulphate and chloride minerals from the aquifer matrix. This study can demonstrate the hydrochemistry assessment guide to support sustainable development in Qasab basin to ensure that adequate groundwater management can play to reduce poverty and support socioeconomic development. 展开更多
关键词 HYDROCHEMISTRY Statistical Analysis Stable Isotopes Inverse Geochemical Modeling and Qasab Basin EGYPT
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黄河上游径流丰枯空间分布特征及其影响因素 被引量:10
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作者 魏伊宁 李勋贵 李芳 《水资源保护》 CAS CSCD 北大核心 2021年第6期103-113,共11页
针对目前青藏高原背景下的区域径流丰枯空间分布特征与其影响因素之间的联系仍不清楚,以及单站点或多站点平均的丰枯指标难以反映区域径流空间分布特征的问题,采用不同时间尺度的标准径流指数,结合经验正交函数、奇异值分解等方法分析... 针对目前青藏高原背景下的区域径流丰枯空间分布特征与其影响因素之间的联系仍不清楚,以及单站点或多站点平均的丰枯指标难以反映区域径流空间分布特征的问题,采用不同时间尺度的标准径流指数,结合经验正交函数、奇异值分解等方法分析了黄河上游1969—2012年径流丰枯的空间分布特征及其与青藏高原降水、气温和积雪3种气象因子的关系。结果表明:黄河上游径流丰枯情况具有区域一致的主要空间分布模态(主要受气象因子的影响)和东北—西南反位相分布的次要空间分布模态(主要受人类活动的影响);夏、秋季比冬、春季更可能出现多年径流量偏丰或偏枯的情形;青藏高原降水、气温和积雪是影响黄河上游径流丰枯空间分布的主要气象因子,降水对径流丰枯变化起主控作用,积雪和气温的季节性影响较明显;青藏高原东北部、东部、北部是影响径流丰枯变化的关键区。 展开更多
关键词 标准径流指数 经验正交函数 奇异值分解 径流丰枯空间分布 黄河上游
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中国西部地区开发区及产业时空变化特征 被引量:10
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作者 付娇 李婧 +1 位作者 贾洪文 黄银洲 《干旱区地理》 CSCD 北大核心 2020年第4期1136-1145,共10页
通过收集中国西部12省份的714个开发区基础数据,采用最邻近距离、核密度分析法以及地理空间分析法,对1993-2015年间中国西部地区(简称西部地区)开发区的空间格局演化规律及产业分布特征展开分析。研究结果表明:(1)西部地区开发区空间集... 通过收集中国西部12省份的714个开发区基础数据,采用最邻近距离、核密度分析法以及地理空间分析法,对1993-2015年间中国西部地区(简称西部地区)开发区的空间格局演化规律及产业分布特征展开分析。研究结果表明:(1)西部地区开发区空间集聚特征显著,呈现出以重点城市和城市圈为依托的“多级集聚”的演变规律。(2)西部地区开发区空间聚集程度和规模均呈现出不断增加的态势,集聚规模增长幅度大于集聚强度。(3)西部地区国家级开发区各类型产业的集聚程度强于省级开发区,集聚规模弱于省级开发区。国家级开发区主要发展资金密集型、技术密集型产业,各类型产业分布格局呈现出单核心集聚特征;省级开发区以劳动密集型、资金密集型产业为主;各类型产业布局特征差距显著,技术密集型呈现出“大集聚、小分散”的分布格局、劳动密集型向中心城市集聚、资金密集型连片规模化发展。研究结果对于西部地区合理利用开发区来加强城市群联系,实现区域协调发展具有一定的现实意义。 展开更多
关键词 开发区 时空演化 主导产业 中国西部地区
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1994—2018年哈萨克斯坦首都圈植被NPP时空变化特征及驱动因素 被引量:4
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作者 陈玉森 艾柯代·艾斯凯尔 +3 位作者 王永东 Talgat ABZHANOV Dani SARSEKOVA Zhazira ZHUMABEKOVA 《干旱区研究》 CSCD 北大核心 2022年第6期1917-1929,共13页
厘清气候变化和人类活动对植被净初级生产力(NPP)的影响,对区域生态系统变化与可持续发展具有重要意义。基于CASA模型,利用1994—2018年5期Landsat遥感影像及气象数据,通过仿真情景实验研究了人类活动和气候变化对哈萨克斯坦首都圈植被... 厘清气候变化和人类活动对植被净初级生产力(NPP)的影响,对区域生态系统变化与可持续发展具有重要意义。基于CASA模型,利用1994—2018年5期Landsat遥感影像及气象数据,通过仿真情景实验研究了人类活动和气候变化对哈萨克斯坦首都圈植被净生产力的影响。结果表明:(1)1994—2018年间,哈萨克斯坦首都圈植被NPP呈波动上升趋势,NPP多年均值为226.21 g C·m^(-2)·a^(-1);(2)首都圈人工造林面积不断增加,对NPP有显著的正增益效果(0.38 Tg C·a^(-1),P<0.01),而气候变化对NPP影响波动比较大,整体上呈现负增益效果(-0.07 Tg C·a^(-1),P=0.34);在土地覆盖变化和气候变化共同作用下,哈萨克斯坦首都圈植被NPP总体上呈显著正增益效果(0.27 Tg C·a^(-1),P<0.1)。相较于气候变化,人类活动对植被净初级生产力影响更加明显,相关性也更强;(3)气候因子中温度、太阳辐射和降水是影响NPP的主要因素。1994—2000年和2006—2012年期间由于温度的升高和降雨量的减少导致NPP损失,分别由218.50 g C·m^(-2)·a^(-1)、201.19 g C·m^(-2)·a^(-1)降到189.00 g C·m^(-2)·a^(-1)、188.48 g C·m^(-2)·a^(-1);2000—2006年和2012—2018年期间随着降水条件的改善,该地区NPP均值显著上升,均值分别达到201.19 g C·m^(-2)·a^(-1)、207.73 g C·m^(-2)·a^(-1)。本文研究结果有助于揭示气候变化和人类活动对植被NPP的影响机制,可为改善荒漠草原区生态环境质量,缓解全球变暖问题和实现哈萨克斯坦2060年碳中和目标提供参考。 展开更多
关键词 CASA模型 NPP 哈萨克斯坦首都圈 PCA分析 仿真实验设计
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Chemical diversity of essential oils from flowers,leaves,and stems of Rhanterium epapposum Oliv. growing in northern border region of Saudi Arabia 被引量:1
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作者 Marwa Awad Abdelrhman Abdelwahab 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2016年第9期767-770,共4页
Objective:To evaluate the medicinal uses of Rhanterium epapposum Oliv.(R.epapposum) growing in northern border region of Saudi Arabia,through the chemical diversity of essential oils extracted from its flowers,leaves ... Objective:To evaluate the medicinal uses of Rhanterium epapposum Oliv.(R.epapposum) growing in northern border region of Saudi Arabia,through the chemical diversity of essential oils extracted from its flowers,leaves and stems.Methods:Aerial parts of R.epapposum were collected in April 2014.Air dried flowers,leaves,and stems were separately subjected to hydrodistillation in a Clevenger-type apparatus for 4 h to extract the essential oils.Gas chromatography-mass spectrometry analysis of the essential oils was carried out using an Agilent 6890 gas chromatograph equipped with an Agilent 5973 mass spectrometric detector.Results:A total of 51 compounds representing 76.35%–94.86% of flowers,leaves and stems oils composition were identified.The chemical profiles of the studied fractions revealed the dominance of monoterpenes,regardless of qualitative and quantitative differences observed.Limonene,linalool,4-terpineol and a-cadinol represented the major constituents of flowers oil.Leaves oil was dominated by limonene,sabinene,a-pinene and b-myrcene whereas linalool,ionole,a-cadinol,b-eudesmol,4-terpineol,and aterpineol were the major constituents of stems oil.Conclusions:Essential oils from flowers,leaves and stems of R.epapposum growing in northern border region of Saudi Arabia are considered as a rich source of monoterpenes which have biological activities. 展开更多
关键词 Rhanterium epapposum Oliv. Asteraceae Essential OILS MONOTERPENES
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Influence of climatic conditions,topography and soil attributes on the spatial distribution of site productivity index of the species rich forests of Jalisco,Mexico 被引量:1
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作者 Adel Mohamed Robin M.Reich +2 位作者 Raj Khosla C.Aguirre-Bravo Martin Mendoza Briseo 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第1期87-95,共9页
This paper presents an approach based on field data to model the spatial distribution of the site productivity index (SPI) of the diverse forest types in Jalisco, Mexico and the response in SPI to site and cli-matic... This paper presents an approach based on field data to model the spatial distribution of the site productivity index (SPI) of the diverse forest types in Jalisco, Mexico and the response in SPI to site and cli-matic conditions. A linear regression model was constructed to test the hypothesis that site and climate variables can be used to predict the SPI of the major forest types in Jalisco. SPI varied significantly with topog-raphy (elevation, aspect and slope), soil attributes (pH, sand and silt), climate (temperature and precipitation zones) and forest type. The most important variable in the model was forest type, which accounted for 35% of the variability in SPI. Temperature and precipitation accounted for 8 to 9% of the variability in SPI while the soil attributes accounted for less than 4% of the variability observed in SPI. No significant differences were detected between the observed and predicted SPI for the individual forest types. The linear regression model was used to develop maps of the spatial variability in predicted SPI for the individual forest types in the state. The spatial site productivity models developed in this study provides a basis for understanding the complex relationship that exists between forest productivity and site and climatic conditions in the state. Findings of this study will assist resource managers in making cost-effective decisions about the management of individual forest types in the state of Jalisco, Mexico. 展开更多
关键词 Best management practices climate change spatial predic-tions tropical dry forests weighted least squares
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<i>In Vitro</i>Evaluation of Some Traits in <i>Stevia rebaudiana</i>(Bertoni) under Drought Stress and Their Relationship on Stevioside Content 被引量:1
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作者 A. E. Badran Mohamed R. A. Abd Alhady Waffa A. Hassan 《American Journal of Plant Sciences》 2015年第5期746-752,共7页
The experiment was conducted to evaluate the differences of plant growth as well as sweetener material of two types of Stevia rebaudiana under conditions of absence and presence of drought stress. In vitro, the experi... The experiment was conducted to evaluate the differences of plant growth as well as sweetener material of two types of Stevia rebaudiana under conditions of absence and presence of drought stress. In vitro, the experiment was conducted as drought traits using four levels of polyethylene glycol (0.0, 10,000, 20,000, 30,000 ppm). It was observed that survival % and No. of shoots should be considered as the important factors associated with stevioside content in stevia plant. According to path coefficient analysis and positive direct effect of studied traits, survival % recorded the highest value (0.5386), whereas No. of shoots recorded the highest value (– 0.8827) as negative direct effect in related to stevioside content. The results showed that all traits were affected, especially under 30,000 ppm level of polyethylene glycol. Generally, the most of studies traits exhibited a recorded clearly difference between the two types and used drought levels on stevia plants. Therefore, selection based on survival % would be more effective to improving stevioside content of stevia plants in drought stress conditions. 展开更多
关键词 STEVIA Drought Stress Polyethylene GLYCOL STEVIOSIDE Path Coefficient
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Trichoderma-Induced Improvement in Growth, Photosynthetic Pigments, Proline, and Glutathione Levels in Cucurbita pepo Seedlings under Salt Stress 被引量:5
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作者 Mona H.Soliman Taghreed S.Alnusaire +5 位作者 Nessreen FAbdelbaky Aisha A.M.Alayafi Mirza Hasanuzzaman Mohamed M.Rowezak Mohamed El-Esawi Amr Elkelish 《Phyton-International Journal of Experimental Botany》 SCIE 2020年第3期473-486,共14页
Salt stress is one of the major abiotic stress in plants.However,traditional approaches are not always efficient in conferring salt tolerance.Experiments were conducted to understand the role of Trichoderma spp.(T.har... Salt stress is one of the major abiotic stress in plants.However,traditional approaches are not always efficient in conferring salt tolerance.Experiments were conducted to understand the role of Trichoderma spp.(T.harzianum and T.viride)in growth,chlorophyll(Chl)synthesis,and proline accumulation of C.pepo exposed to salinity stress.There were three salt stress(50,100,and 150 mM NaCl)lavels and three different Trichoderma inoculation viz.T.harzianum,T.viride,and T.harzianum+T.viride.Salt stress significantly declined the growth in terms of the shoot and root lengths;however,it was improved by the inoculation of Trichoderma spp.C.pepo inoculated with Trichoderma exhibited increased synthesis of pigments like chl a,chl b,carotenoids,and anthocyanins under normal conditions.It was interesting to observe that such positive effects were maintained under salt-stressed conditions,as reflected by the amelioration of the salinity-mediated decline in growth,physiology and antioxidant defense.The inoculation of Trichoderma spp.enhanced the synthesis of proline,glutathione,proteins and increased the relative water content.In addition,Trichoderma inoculation increased membrane stability and reduced the generation of hydrogen peroxide.Therefore,Trichoderma spp.can be exploited either individually or in combination to enhance the growth and physiology of C.pepo under saline conditions. 展开更多
关键词 Vegetable crop antioxidant PROLINE NaCl CUCURBITA plant-microbe interaction
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Physicochemical and Bacteriological Quality of Groundwater, East of Nile Delta of Egypt 被引量:1
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作者 Muhammad Gomaah Amany Ramadan Mona M. El-Shazly 《Journal of Geoscience and Environment Protection》 2021年第1期97-106,共10页
Groundwater is an important source of freshwater for drinking and irrigation purposes, and hence protecting it against depletion and deterioration is extremely required. Groundwater could get contaminated physically, ... Groundwater is an important source of freshwater for drinking and irrigation purposes, and hence protecting it against depletion and deterioration is extremely required. Groundwater could get contaminated physically, chemically, or microbiologically. Each type of contamination is linked to different sources and in turn imposes different types of health problems and consequences. A water sample from Bahr Al-Baqar Wastewater drain and 13 groundwater samples were collected for physiochemical and bacteriological analyses to evaluate groundwater contamination in As-Salihiyyah and adjacent areas, east of Nile Delta of Egypt. Nitrate, COD, and BOD values collected from Bahr Al-Baqr drain and groundwater exceeded the Egyptian maximum permissible limit for drinking water (0.5, 6, 10, respectively). The total number of viable microorganisms (TVC) test for Bahr Al-Baqar drain was recorded as more than 300 CFU/mL, and the total coliform recorded 1100 MPN/100ml, indicating high level of contamination. The high count of the TVC (16-↑300 CFU/mL) for groundwater and the total coliform (3 - 1100 MPN/100ml) indicated that groundwater is contaminated and unsafe for drinking and might be affected by Bahr Al-Baqar wastewater drain. 展开更多
关键词 East of Nile Delta Bahr Al-Baqar Groundwater Contamination
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Using Automation Controller System and Simulation Program for Testing Closed Circuits of Mini-Sprinkler Irrigation System 被引量:2
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作者 Hani A. Mansour Hany M. Mehanna +1 位作者 Mohamed E. El-Hagarey Ahmehd S. Hassan 《Open Journal of Modelling and Simulation》 2013年第2期14-23,共10页
The field experiments were conducted at the experimental farm of Faculty of agricultural, southern Illinois University SIUC, USA. The project makes the irrigation automated. With the use of low cost sensors and the si... The field experiments were conducted at the experimental farm of Faculty of agricultural, southern Illinois University SIUC, USA. The project makes the irrigation automated. With the use of low cost sensors and the simple circuitry makes currently project a low cost product, which can be bought even by a poor farmer. This research work is best suited for places where water is scares and has to be used in limited quantity and this proposal is a model to modernize the agriculture industries at a mass scale with optimum expenditure. In the field of agricultural engineering, use of sensor method of irrigation operation is important and it is well known that closed circuits of Mini-sprinkler irrigation system are very economical and efficient. Closed circuits are considered one of the modifications of Mini-sprinkler irrigation system, and added advantages to Mini-sprinkler irrigation system because it can relieve low operating pressures problem at the end of the lateral lines. In the conventional closed circuits of Mini-sprinkler irrigation system, the farmer has to keep watch on irrigation timetable, which is different for different crops. Using this system, one can save manpower, water to improve production and ultimately profit. The data could be summarized in following: Irrigation methods under study when using lateral length 60 mcould be ranked in the following ascending order according the values of the predicted and measured head losses CM1M-SIS CM2M-SIS.The correlation (Corr.) coefficients were used to compare the predicted and measured head losses along the lateral lines of all the closed circuits designs. Generally, the values of correlation analysis were (>0.90) were obtained with 0% field slope60 mlength (experimental conditions) for all closed circuits.The interaction between irrigation methods: at the start there are significant differences between CM2M-SIS and CM1M-SIS. 展开更多
关键词 Automation Controller Simulation Program Mini-Sprinkler IRRIGATION LATERAL CLOSED CIRCUITS
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The Geothermal Regime in Sirt Basin, Libya: The Geological Role and Heat Flow Studies
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作者 Ahmed Al-Rashed Fouad Shaaban Ahmed Yousef 《International Journal of Geosciences》 2019年第1期57-79,共23页
Bottom hole temperatures (BHTs) and static formation temperatures (DSTs) of 70 deep exploratory wells are used to evaluate the geothermal regime in the northeastern part of Sirt Basin. A linear regression was derived ... Bottom hole temperatures (BHTs) and static formation temperatures (DSTs) of 70 deep exploratory wells are used to evaluate the geothermal regime in the northeastern part of Sirt Basin. A linear regression was derived between the BHT’s and the DST’s, for correcting the bottom hole temperatures from the drilling factors that lower them from the true formation temperatures. The geothermal gradients were calculated using the corrected BHT’s and the heat flow has been estimated. Interpretation of the geothermal data, utilizing subsurface maps and isothermal geologic cross section, revealed a shallow, local semi-thermal reservoir of Oligo-Miocene age (at depths 1000 m). The geothermal gradients and heat flow values of this reservoir are ranging from 40 - >60°C/Km and from 80 up to >130 mW/m2, respectively. At deeper depths (>1000 m until the maximum depth of investigation), the area has more or less moderate to low geothermal gradients that range from 40 to 2. The study indicates that the vertical and the lateral variations of the formation temperatures, geothermal gradients and the heat flow values are controlled by the structural, groundwater movements as well as lithological and thermal characteristics of the subsurface sequence. 展开更多
关键词 GEOTHERMAL Reservoir BOTTOM Hole TEMPERATURES Static Formation TEMPERATURES Heat Flow SIRT BASIN
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Hydrochemistry of Umm Er Radhuma Groundwater
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作者 Muhammad Gomaah 《Journal of Geoscience and Environment Protection》 2021年第4期128-146,共19页
Umm Er Radhuma Aquifer (UER) is the most important groundwater aquifer in Saudi Arabia, extending over 1.6 M<span style="font-size:10.5pt;font-family:;" "=""><span style="color:#... Umm Er Radhuma Aquifer (UER) is the most important groundwater aquifer in Saudi Arabia, extending over 1.6 M<span style="font-size:10.5pt;font-family:;" "=""><span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"=""><span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">·</span></span></span>km<sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"> in the eastern part of the Arabian Peninsula, forming the main aquifer throughout the Rub’ Al-Khali (RAK). </span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">Groundwater salinity increased from west to east, reaching more than 27,000 mg/L near the border with the United Arab Emirates, where a Na</span><sup><span style="font-family:Verdana;">+</span></sup><span style="font-family:Verdana;">-Ca</span><sup><span style="font-family:Verdana;">2+</span></sup><span style="font-family:Verdana;">Cl<span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">ˉ</span></span><span style="font-family:Verdana;">-<img src="Edit_c1bbc858-a8a7-45ca-be57-e2bb456cbddb.bmp" alt="" /></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> </span></span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">water type dominated. Gibbs diagrams indicated that the dissolution/precipitation of carbonates and evaporation/precipitation of minerals, especially anhydrite, gypsum, and halite account for the solutes and salinity in groundwater. Most of the samples plot above the 1:1 line of (Ca</span><sup><span style="font-family:Verdana;">2+</span></sup><span style="font-family:Verdana;"> + Mg</span><sup><span style="font-family:Verdana;">2+</span></sup><span style="font-family:Verdana;">) against <img src="Edit_5405b197-c8d5-436d-8648-dd95afefb8e6.bmp" alt="" /></span></span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">, indicating other sources of Ca</span><sup><span style="font-family:Verdana;">2+</span></sup><span style="font-family:Verdana;"> and Mg</span><sup><span style="font-family:Verdana;">2+</span></sup><span style="font-family:Verdana;"> in the groundwater along with dolomite and calcium carbonate minerals. Phreeqc model indicated that the main clay minerals are kaolinite and gibbsite which had major effect on the cation exchange process as indicated by the Chloro-Alkaline index (CAI), where most of groundwater samples had values greater than zero which indicated the occurrence of reverse ion exchange between the groundwater and its host aquifer. The water type Na</span><sup><span style="font-family:Verdana;">+</span></sup><span style="font-family:Verdana;">-Ca</span><sup><span style="font-family:Verdana;">2+</span></sup><span style="font-family:Verdana;">Cl</span><sup><span style="font-family:Verdana;"><span style="color:#4F4F4F;font-family:-apple-system, " font-size:16px;white-space:normal;background-color:#f7f7f7;"="">ˉ</span></span></sup><span style="font-family:Verdana;">-<img src="Edit_e8c17a28-24a8-4e14-a615-24c0e0817331.bmp" alt="" /></span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">dominated in the eastern part of the aquifer as the anaerobic conditions prevailed and the reduction of sulphate took place.</span></span></span></span> 展开更多
关键词 HYDROCHEMISTRY Umm Er Radhumma Aquifer GROUNDWATER Water-Rock Interaction
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Inhibition of Ehrlich Ascites Carcinoma by Lactuca serriola in Swiss Albino Mice
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作者 Mona Alshathly Eman Elsharkawy 《Journal of Chemistry and Chemical Engineering》 2014年第1期66-71,共6页
To evaluate the antitumor activity of Lactuca serriola against EAC (Ehrlich ascites carcinoma) in Swiss albino mice. The in vivo antitumor activity of the methanol extract of plant Lactuca serriola was evaluated at ... To evaluate the antitumor activity of Lactuca serriola against EAC (Ehrlich ascites carcinoma) in Swiss albino mice. The in vivo antitumor activity of the methanol extract of plant Lactuca serriola was evaluated at (100 mg/kg and 200 mg/kg of hole plant and 200 mg/kg, 400 mg/kg of fruit bw) against EAC using mean survival time. After administration of the extracts of Lactuca serriola, viable EAC cell count and body weight in the EAC tumor hosts were observed. The animal was also observed for improvement in the hematological parameters (e.g., hemoglobin content, red and white blood cells count and differential cell count) after treatment of plant extract. Intraperitoneal administration of plant extracts reduced viable EAC cells, increased the survival time and restored altered hematological parameters. Significant efficacy was observed for fruit extract at high concentration 400 mg/kg dose (P 〈 0.05). It can be concluded that the methyl extract ofLactuca serriola possesses significant antitumor activity. 展开更多
关键词 Antitumor activity Lactuca serriola EAC hematological parameter.
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Soil Characteristics Influence the Selection of Dominant Plant Genotypes Inhabiting Wadi Sudr, Egypt
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作者 Esraa Attia El Sherbeny Amal Ahmed Morsy Mahmoud Magdy 《American Journal of Plant Sciences》 2016年第8期1304-1315,共12页
Rangeland plant community and species composition are known to be related to specific soil properties. The current study investigated the ecological influence (soil characteristics) on the selection and distribution o... Rangeland plant community and species composition are known to be related to specific soil properties. The current study investigated the ecological influence (soil characteristics) on the selection and distribution of ecological-related genotypes of dominant xerophyte species in WadiSudr of Egypt. AFLP analysis reflected the genetic profile of the samples species from two altitudinal ranges (up and midstream) and was compared statistically with the differences of their inhabiting soil characteristics on two depth levels (20 and 40 cm) using Mantel test. Correlation values (r) ranged from 0.585 - 0.778 when treating the physical and chemical properties of soil samples regardless its altitudinal area. The correlation confirms that the soil chemical and physical properties influence the selection of a certain genotypes of the dominant xerophytes plants collected from Wadi Sudr of Egypt to certain altitude, while depths at 20 and 40 cm play a key role in the early growth and then the colonization of the selected genotypes, respectively. More studies are needed to exactly test the role and the importance of each of the correlated property to the plant growth and colonization. 展开更多
关键词 Xerophytes Wadi Sudr-Egypt Soil Characteristics F-AFLP Mantel Test
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Transgenic Date Palm Containing Endotoxin Cry3Aa Gene
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作者 Awatef Mahmoud Badr-Elden Ibrahim Abd El-Maksoud Ibrahim +3 位作者 Hamdy Ahmed Emaral Mahdia Farid Gabr Ahmed Abbas Nower Tamer Mahfouz Abd Elaziem 《Journal of Agricultural Science and Technology(A)》 2017年第4期246-257,共12页
Date palm, like all other crops, is very sensitive to the injury by many insect pests, which may lead to the death of the affected plant and causes decrease in yield. In the present study, an efficient Agrobacterium f... Date palm, like all other crops, is very sensitive to the injury by many insect pests, which may lead to the death of the affected plant and causes decrease in yield. In the present study, an efficient Agrobacterium for genetic transformation was successfully achieved for well known date palm (Phoenix dactylifera L.) cv. Medjool and Khalas using callus as explant. Embryogenic callus were recorded 100% mortality when cultured on MS medium containing 100 mg/L kanamycin with different cultivars, thus it was chosen for the selection of transformed explants. Embryogenic callus of Medjool and Khalas were incubated with Agrobacterium tumefaciens strain LBA 4404 for 0.5, 1, 2, 4 and 24 h on LB medium. After the incubation periods, embryogenic callus was transferred to MS medium with 0.1 mg/L NAA, 0.05 mg/L BA, 250 mg/L carbenicillin and 100 mg/L kanamycin for detection of transgenic embryogenic callus. Polymerase chain reaction (PCR) was used for the rapid screening of Cry3Aa gene. For screening, total genomic DNA was isolated from transformants. Using primer specific to Cry3Aa gene (forward and reverse), a PCR product with a size of about 2,000 bp was amplified when all nucleic acid from the transformants were utilized as templates. PCR analysis confirmed the appearance of the transgene of 2,000 bp in one individual plantlet. Presence and integration of foreign Cry3Aa gene in regenerated kanamycin resistant embryogenic callus was also confirmed by Southern blot hybridization. It was found that one transgenic embryogenic callus for both Medjool and Khalas showed a single copy of gene integration. These results signify the successful transfer of Cry3Aa gene into date palm plant. 展开更多
关键词 Date palm Agrobacterium tumefaciens Cry3Aa gene Southern blot analysis transformation.
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Inter-Specific Biochemical Diversity between <i>Echis pyramidum</i>and <i>Eryx colubrinus</i>Inhabiting El-Faiyum, Egypt
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作者 Mohamed A. M. Kadry Eman M. E. Mohallal +1 位作者 Doha M. M. Sleem Mohamed A. S. Marie 《Advances in Bioscience and Biotechnology》 2015年第8期495-500,共6页
Discontinuous polyacrylamide gel electrophoreses for lactate dehydrogenase (Ldh) and alfa-esterase (α-Est) isoenzymes were conducted for biochemical differentiation between Echis pyramidum and Eryx colubrinus inhabit... Discontinuous polyacrylamide gel electrophoreses for lactate dehydrogenase (Ldh) and alfa-esterase (α-Est) isoenzymes were conducted for biochemical differentiation between Echis pyramidum and Eryx colubrinus inhabiting El-Faiyum, Egypt. Total lipids and total protein of liver and muscle tissues in both species were also analyzed. Three Ldh isoforms were recorded in both species and the activity and relative front (RF) of Ldh-1 seemed to be higher in E. pyramidum than in E. colubrinus. This high activity could be supported by the significant increase in the total lipids and total protein in liver and muscle tissues of this species. It is thus possibly reasonable to suppose that E. pyramidum is more active, energetic and adaptable in its habitat than E. colubrinus. α-Est showed five isozymic forms fractions in E. pyramidum, while it showed only four isoforms in E. colubrinus. α-Est-1 was the first clear, dense and thick isoform in E. pyramidum, but it was completely absent in E. colubrinus. High activity of the esterase isoform;α-Est-1 only in the heart tissue of E. pyramidum may reflect the high ability of E. pyramidum to be more resistant to the accumulated toxic residues in its body tissues than E. colubrinus. 展开更多
关键词 Echis pyramidum (Viperidae) Eryx colubrinus (Boidae) Ldh ISOENZYME Est ISOENZYME Total LIPIDS
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