Ras El Hekma Research Articles

Expected potential hemipteran vectors of Xylella fastidiosa bacterium in olive and vineyard groves of the Egyptian northwestern coast

Xylella fastidiosa was recently added to the list of threatening pathogens affecting more than 300 plant hosts. Hemipteran hoppers that feed on xylem have been documented as potential transmitters. Hemipteran hoppers, known vectors for plant pathogens via xylem feeding, pose significant risks to agriculture. Despite their role in transmitting diseases, comprehensive data on their species diversity, distribution, and seasonal patterns, particularly in critical agricultural zones, remain sparse. Hence, the current study was carried out at 14 sites (eight olive farms and six vineyards) during the 2021/2022 season to develop a comprehensive checklist of hopper species present on the Egyptian Northwestern Coast, including their seasonal and location distribution, to serve as a real roadmap supporting control strategies if the pathogen breaches Egyptian borders. Utilizing 560 yellow sticky traps, we collected data seasonally, resulting in the identification of 21 hopper species belonging to 14 genera within four families. Olive orchards harbored a higher number of hoppers compared to vineyards, with Empoasca decipiens being the most dominant species. Our findings provide a foundational checklist and highlight the importance of continued monitoring and detailed studies to support proactive control strategies against potential X. fastidiosa outbreaks. We used 560 yellow sticky traps at 10 traps per site (80 traps for olive orchards and 60 traps for the vineyard per season) throughout the study period. Traps were installed at two levels to catch hopper species harboring tree canopies and ground vegetation. Each trap was replaced every 7 days, and the collected trap sheets were sent to the laboratory for segregation and identification. The data revealed 21 hopper species belonging to 14 genera and 4 families, with cicadellid species being the most represented (14 species). Olive orchards harbored a higher number of hoppers than vineyards. Empoasca decipiens exhibited the highest dominance among the remaining species. Although summer sampling yielded the highest number of hopper species and trapped specimens, seasonal variation in the distribution pattern exhibited non-significant differences (F = 1.7 and P = 0.173). Ras El-Hekma had the highest species representation (21 species), whereas El-Negala had the highest species richness. The lowest species representation at the Barrani location had the highest abundance of caught specimens. Although there were fluctuations in the trapped specimens among the examined locations, statistical analysis revealed no significant differences (F = 0.67, P = 0.58). Cluster analysis revealed distinct groupings with different degrees of similarity for both seasonal and location distributions. The impact of trap height on the hopper capture pattern showed a biased tendency towards low traps. Diversity indices showed no significant differences between the examined locations. Although our results offer a foundation for potential control strategies against X. fastidiosa, further detailed studies are required to fill the knowledge gap regarding its suspected vectors. Such research will guide management strategies that can be applied in cases where this infectious bacterium crosses Egyptian borders.

Trace Elements Characterization in Rocks Using Neutron Activation Analysis, Northwestern Coast, Ras El-Hekma–Egypt

Trace Elements Characterization in Rocks Using Neutron Activation Analysis, Northwestern Coast, Ras El-Hekma–Egypt

Multi-decadal coastal change detection using remote sensing: the Mediterranean coast of Egypt between El-Dabaa and Ras El-Hekma

A key source of information for many decision support systems is identifying land use and land cover (LULC) based on remote sensing data. Land conservation, sustainable development, and water resource management all benefit from the knowledge obtained from detecting changes in land use and land cover. The present study aims to investigate the multi-decadal coastal change detection for Ras El-Hekma and El-Dabaa area along the Mediterranean coast of Egypt, a multi-sectoral development area. Besides, the superiority of the area is highly dependent on its proximity to three development projects: the tourism and urban growth pole at Ras El-Hekma, the beachfront Alamain New Mega City, and the Nuclear Power Plant at El Dabaa. This study utilized multi-spectral Landsat satellite images covering 1990, 2010, and 2020 to perceive the post-classification change detection analysis of the land use and land cover changes (LULCC) over 30 years. The results of the supervised classification from 1990 to 2020 showed a 47.33 km2 (4.13%) expansion of the agricultural land area, whereas the bare soil land area shrunk to 73.13 km2 (6.24%). On the other hand, the built-up activities in the area launched in 2010 and escalated to 20.51 km2(1.77%) in 2020. The change in land use reveals the shift in the economic growth pattern in the last decade toward tourism and urban development. Meanwhile, it indicates that no conflict has yet arisen regarding the land use between the expanded socioeconomic main sectors (i.e., agriculture, and tourism). Therefore, the best practices of land use management and active participation of the stakeholders and the local community should be enhanced to achieve sustainability and avoid future conflicts. An area-specific plan including resource conservation measures and the provision of livelihood alternatives should be formulated within the National Integrated Coastal Zone Management (ICZM) plan with the participation of the main stakeholders and beneficiaries. The findings of the present work may be considered useful for sustainable management and supportive to the decision-making process for the sustainable development of this area.

Stacked machine learning models for predicting species richness and endemism for Mediterranean endemic plants in the Mareotis subsector in Egypt

An effective method for identifying species and evaluating the effects of changes caused by humans on specific species is the application of species distribution modelling (SDM) in desert environments. The fact that many dry lands and deserts throughout the world are situated in inhospitable regions may be the reason why such applications are still infrequently used on plant species in Egypt's Mediterranean region. Henceforth, the current study aims to map species richness and weighted endemism of Mediterranean endemics in the Mareotis subsector in Egypt and determine the environmental variables influencing distribution of these taxa. We produced a map of species distribution range using Ensemble SDMs. Further, stacked machine learning ensemble models derived from Random Forest (RF) and MaxEnt models were applied on 382 Mediterranean endemics distribution data to estimate and map diversity and endemism using two indices: species richness (SR) and weighted endemism index (WEI). The best models for ensemble modelling were chosen based on Kappa values and the Area Under the Receiver Operator Curve (AUC). The results showed that the models had a good predictive ability (Area Under the Curve (AUC) for all SDMs was > 0.75), indicating high accuracy in forecasting the potential geographic distribution of Mediterranean endemics. The main bioclimatic variables that impacted potential distributions of most species were wind speed, elevation and minimum temperature of coldest month. According to our models, six hotspots were determined for Mediterranean endemics in the present study. The highest species richness was recorded in Sallum, Matrouh wadis and Omayed, followed by Burg El-Arab, Ras El-Hekma and Lake Mariut. Indeed, species richness and endemism hotspots are promising areas for conservation planning. This study can help shape policy and mitigation efforts to protect and preserve Mediterranean endemics in the coastal desert of Egypt. These hotspots should be focused on by policy makers and stakeholders and declared as protectorates in the region. The largest number of species per area would be protected by focusing primarily on the hotspots with high species richness.

Shoreline displacement along the Mediterranean coast of Egypt between El-Dabaa – Ras El-Hekma

The study of the shoreline erosion, accretion, and instability along the northwestern Mediterranean coast of Egypt between El-Dabaa – Ras El-Hekma was achieved using Digital Shoreline Analysis System (DSAS) software. The erosional/accretional changes were quantified via the End Point Rate (EPR) and Net Shoreline Movement (NSM) statistical parameters. To analyze and compute the magnitude of the shoreline displacement for the study area, three different intervals were adopted; these are long-term change (for one interval from 1990 to 2020), short-term changes (for three intervals: 1990–2000, 2000–2010, and 2010–2020), and seasonal change (for every 6 months from summer 2019 to winter 2020). Results revealed that the shoreline erosion was dominant over long-term change (1990–2020) showing an increase from −0.31 m/yr to −27.83 m/yr. The short-term shoreline analysis for the period from 1990 to 2020 with a 10-year time interval shows that the average rate changes during the first, second, and third intervals were −0.47 m/yr, −0.06 m/yr, and −1.12 m/yr; respectively. Finally, the average rate of shoreline change over the total period (1990–2020) was estimated at −0.55 m/yr. Accordingly, shoreline erosion is the dominant pattern in the study area. This erosion is mainly dependent on the major activities of unplanned coastal development. The main threats posed by the anthropogenic activities in the area are uncontrolled coastal urbanization, the lack of commitment to the setback regulations for building constructions, and the development of tourism resorts and recreational facilities which leads to habitat loss and the destruction of the natural protection system of the shore (dune).

Potential of wind energy and economic assessment in Egypt considering optimal hub height by equilibrium optimizer

In Egypt, the wind market increases quickly to make it one of the top countries in the Middle East. This study discusses the viability of wind resources and the economic assessment for four locations in Egypt: Ras El-Hekma, Farafra, Nuweiba, and Aswan through two stages. In the first stage, the optimal hub height for some wind turbines has been calculated by using Equilibrium Optimizer (EO) algorithm to achieve maximum wind energy with overall minimum cost. The second stage, the economic assessment has been evaluated by using such turbines to calculate the cost of energy (COE) compared to the global and Egyptian production costs of wind energy. Developed MATLAB programs are applied for statistical analysis of wind data. The results have shown that Ras El-Hekma’s average wind speed is higher than other sites and its wind energy potential is the best. Moreover, the economic assessment for selected locations turns out that Ras El-Hekma by using EWT-DW61/22 turbine has the lowest COE.

Assessment of erosion rate in a rainfed agricultural area on the Northwestern coast of Egypt using 137Cs measurements

In the present work, the use of the fallout radionuclide 137Cs as a tracer for estimating soil redistribution rates over the past 60 years was tested in Egypt at an agricultural field with a smooth slope (0–10%) located in Ras El-Hekma on the Northwestern coast. The average annual soil erosion rate was derived from 137Cs inventories (Bq m−2) and by using the conversion Diffusion and Migration Model (DMM). The activity concentrations of 137Cs with uncertainty ranging between 7.5 and 20.9% were measured using HPGe gamma spectrometry. Approximately exponential shape for the distribution of 137Cs activity concentration was observed within the upper 20 cm of the soil profile associated with the reference site while for the study sites, the 137Cs depth distribution profiles indicate generally an increase of activity reaching a maximum peak of 137Cs usually at a depth of 10–15 cm followed by an abrupt exponential decrease of 137Cs activity concentration with depth. The measured average reference inventory for this area was 697 Bq m−2 with a coefficient of variation of 23%. This value is close to the estimated reference inventory using the conversion model, which was 744 Bq m−2. Transect sampling strategy was adopted at the study area where three parallel transects were chosen based on the common slope. The estimated average annual erosion rate for the three transects was found to be 7.5 t ha−1 y−1, and sediment delivery ratio was approximately 98%, which shows the moderate vulnerability of the Ras El-Hekma area to water erosion.

Application of Shannon and Simpson Diversity Index to Study Plant biodiversity on Coastal Rocky Ridges Habitats with Reference to Census Data in the Ras El-Hekma and Omayed Area on the Western Coastal Region of Egypt

Biodiversity is a word recently introduced by experts in field of biology, and it is important for ecosystem health and productivity, biodiversity is one of the primary interests of ecologists, and the widely used diversity indices are Shannon’s and Simpson’s index. This study aims to characterize the plant communities and to identify and compare the plant species diversity in the Ras El-Hekma area and Omayed protectorate. The results of the application of the indices of plant biodiversity in both the Ras El-Hekma area and the Omayed protectorate showed that the value of the Shannon index ( H' ) 2.058 and 2. 322, the value of the Simpson index ( D ) 0.85 and 0.92, the value of the Evenness index ( E ) 0.89 and 0.96, the value of Effective Number of Species ( ENSSh , ENSSi ) 6.66, 7.83 and 12.5, 10.19 respectively. The results demonstrated the highest values were recorded in the community of Omayed protectorate compared with the Ras El-Hekma area. The results also revealed that ( H' ) in the two communities 2 ≥ H' < 3. According to the criteria of diversity index, they were moderate diversity. As for the Evenness index (E), 0.75 >E ≤ 1. According to the categorized of the Evenness index, both are stable community.Through the results, diversity indices indicate that there is a more diverse community in the Omayed protectorate compared with the Ras El-Hekma area. The reason may be due to the individuals in Omayed was more evenly distributed among the species than the individuals in Ras El-Hekma. Based on the interpretation of the criteria and categories of Shannon, Simpson, Evenness and Effective Number of Species indices, this meant that the Omayed had high environmental wellness and biodiversity level. Both indices are more reflective in nature and can predict the ecosystem health. Therefore, it may be good to have one of these biodiversity indices to be used for plant communities to understand the ecosystem healthiness in the habitats.

Comparative Study of Landform Mapping Using Terrain Attributes and Topographic Position Index (TPI): a Case Study in Al-Alamien – Ras El-Hekma Region, Egypt

The aim of this study is to compare the classification of the landscape of the area located between Al-Alamien and Ras El-Hekma to landform classes using two different classification methods; the terrain attributes method and the topographic position index (TPI) method. Terrain attributes classification method derived from a digital elevation model and were overlaid using cell statistics to generate a landform map with seven classes. The landform classes were: (1) Lower coastal plain (17.86%), (2) Upper coastal plain (43.61%), (3) Piedmont plain (2.33%), (4) Dissected escarpment (2.64%), (5) Plateau (26.79%), (6) Ridges and coastal bars (3.62%), and (7) Inland dunes (3.15%). The topographic position index (TPI) method which generate the landform classes uses only the digital elevation model. The generated landform classes were: (1) Valleys (2.1%), (2) Midslopes drainages and shallow valleys (1.1%), (3) Plains (92.77%), (4) Hills in plains (0.34%), (5) Mesas (2.44%), and (6) Ridges (1.25%). The comparison of the two methods showed that using the terrain attributes method was more detailed.

English

A numerical model of variable-density groundwater flow and miscible salt transport is applied to investigate the extent of seawater intrusion in coastal aquifer of Ras El-Hekma, northwestern coast, Egypt. The SEAWAT 2000 code is used to solve the density-dependent groundwater flow and solute transport governing equations. Seventeen groundwater samples were collected in 2015 for routine chemical analysis and water level monitoring were carried out and interpreted. The model was calibrated using data measured for heads (m) and TDS (mg/L) in 2009 compared with data collected in 2015. Three scenarios of pumping and fourth scenarios of sea level rise by 0.5 m were applied. The results of three scenarios of pumping revealed that there was a general trend of drawdown in water table (~5 m) of observed wells located at about 1 to 1.5 km from the coast at the end of 20 years of simulation. At the same time there was replenishment from rainfall and surface runoff caused a water table rise in some observed wells that were located inland. For the proposed fourth scenario of sea level rise, the seawater/freshwater interface will migrate more inland (0.5 to 2 km) than its current position. The result of the numerical model shows a transgression of seawater inland and along the coast. The model and chemical results recommend a decrease in pumping to the drilled wells should not exceed 40 m3/day in order to avoid further seawater intrusion along the coast and upwelling of deep saline groundwater with continuous monitoring of the groundwater level and salinity measurements in north coast of Mediterranean Sea. Key words: Seawater intrusion, groundwater modeling, SEAWAT code, Ras El-Hekma, Egypt.

Integrative management of saltwater intrusion in poorly-constrained semi-arid coastal aquifer at Ras El-Hekma, Northwestern Coast, Egypt

Saltwater intrusion is a major concern in coastal aquifers, particularly in arid and semiarid regions, where recharge is limited and groundwater withdrawal is the main source of potable water. In Ras El Hekma groundwater occurs in the Pleistocene aquifer as a thin lens of freshwater where groundwater quality is very sensitive to pumping stresses. High groundwater withdrawals from the Pleistocene aquifer deteriorate the groundwater quality along the coast due to upwelling of saltwater into the thin lens freshwater. The Pleistocene aquifer is poorly-constrained; the hydrological and geochemical records are sparse. Therefore, a simple analytical approach has been used in order to address local and regional groundwater management issues, for cases of data scarcity using little known and well defined parameters. The model assumes steady state flow as an initial condition in an isotropic and homogeneous medium, with a sharp interface between the freshwater and seawater wedge. The model combines the hydrogeological and geochemical characterization, adapted to the aquifer geometry, in order to provide global salt and freshwater balances to the Ras El Hekma scale site. The model shows progressive extension of the seawater intrusion zone (x-toe) upon increasing the groundwater withdrawals from 250m3/day to an order of magnitude of this amount. The x-toe distance has been extended from 1700 to 5000m from the tip of Ras El Hekma to inland. Such model could be applied to estimate the volume of the freshwater and seawater wedge along the coast as well as to predict the groundwater withdrawals under different pumping scenarios. Seawater intrusion, in the Ras El Hekma area, is caused by the unbalance between the pumping withdrawal rates and the natural recharge from precipitation. The model can be applied for similar hydrogeological systems, specifically, coastal aquifers located in semiarid to arid environments where limited aquifer data is available.

EVALUATION OF GROUNDWATER SUITABILITY FOR DRINKING AND AGRICULTURE USE IN THE AREA BETWEEN EL DABAA AND RAS EL HEKMA, NORTHWESTERN COAST, EGYPT.

Recent industrial and urban activities have led to elevated concentrations of a wide range of contaminants in groundwater, which affect the health of million people worldwide. Groundwater is the major source for drinking and agriculture uses in the Northwestern coast of Egypt. Forty five groundwater samples representing the Pleistocene and the Middle Miocene aquifers were collected from the area between El-Dabaa and Ras El-Hekma. Samples were analyzed for total dissolved solids, calcium, magnesium, sodium and five heavy metals including; aluminum, iron, manganese, copper, and lead, using the standard methods. The results show that, the total dissolved solids; calcium, magnesium and sodium concentrations have mean values of 8426, 264.5, 295.9 and 2390.1 mg/l, respectively. The heavy metals show high concentrations in groundwater of Pleistocene and Middle Miocene aquifers. The concentration of iron recorded the mean of 1.99 mg/l followed by aluminum 0.45 mg/l, while manganese recorded the lowest mean value of 0.09 mg/l. The results show that, the majority of groundwater samples in different aquifers are unsuitable for human drinking due to high concentrations of total salinity, major ions and heavy metal constituents. According to the international standards recommended by the National Academy of science (NAS) and National Academy of Engineering (NAE) the groundwater samples in the study area ranges from an excellent to not acceptable classes for the livestock and poultry uses. Most of the groundwater samples in the Pleistocene aquifer (88%) are unsuitable for domestic and laundry uses as the total hardness values are exceeding 300 mg/l, however; all the Middle Miocene groundwater are unsuitable for domestic and laundry uses. Whereas, 71% of the total samples are unsuitable for irrigation according to total dissolved solids and about 93% of groundwater samples are unsuitable for domestic and laundry uses according to total hardness. The groundwater samples tapping the available aquifers in the study area have to go through treatment and desalination processes using suitable and economical applied methods to enhance the groundwater quality and be considered as suitable for different uses.

AN ECONOMIC STUDY OF THE MOST IMPORTANT RAIN-FED PLANT MATROUH GOVERNORATE

The present study was conducted at Matrouh Governorate, where the area exlends along the coastal plain southward depth 2.5 km (at El Alamien) and disappears in other places, i.e. Fuka and Ras El-Hekma. Due south the coastel phin the plateau rises gradually until Siwa Oasis, where the altitude falls down to around 27 m below sea level. The study aims at evaluating the agricultural resources availability of irrigation water resoures, arable land, the current status of the rainfed agricultural system adopted, in addition to productive and economic efficiency assessment. The study indicited that the net yield of irrigated wheat crops was 2210 pounds/acre, while the net return of the opportunity cost of about 492.8 pounds/acre, while showing that the opportunity cost of agriculture represents the best investment opportunity rain-fed wheat crop cultivated rainy system, where there has been a return of about 151.9 pounds/acre, while they cause the loss of about 460 pounds/acre. Also, data showed that the net yield of the irrigated olive crops was about 6450 pounds/acre, while the net return of the opportunity costs of about 1636.9 pounds/acre, which means productive activity preference for the cultivation of the crop olive about the opportunity cost of this activity represents a better investment opportunity. This study has led to some recommendations, including the need to develop a specific time-plan for the establishment of infrastructures helping in rain water harvesting and provisim. Altmioalah sources needed to identify dams and reservoirs needed for the absorption and maintenance and rainwater.

IMPACT OF RAINFALL TEMPORAL VARIABILITY ON RAINFED MAJOR FOOD CROPS AND AGRONOMIC PRACTICES IN THE NORTH WESTERN COASTAL ZONE OF EGYPT

High variability in rainfall amount and occurrence are the main constraints for crop production in rainfed arid and semi-arid areas. Precipitation data analysis focusing on rainfall amount, distribution and dry spells is of a great importance to mitigate the drought impact on crop production. In this study, we used the very, easily accessed daily data from the National Center for Environmental Prediction; Climate Forecast System Reanalysis (NCEP/CFSR) for a period of 35 years (1979-2014) over the North Western Coast (NWCZ) of Egypt at four locations: Ras El Hekma, Matrouh, El Neguilla and Barrani. The data of total annual rainfall, maximum daily data and the number of rainy days based on 0.1,5,10,15 mm of rain, long and short dry spells and the start of the rainy season were presented. The analysis of the dry spells showed that there are at least 6 to 7 dry spells of 10 days or longer each year with a probability exceeding 20% in all the locations studied. Data also showed that Barrani has the highest total annual precipitation and maximum daily precipitation of 182 mm and 45 mm, respectively. A number of the rainy days of the four examined thresholds of 0.1,5,10 and 15 mm were higher in Barrani as compared to the other three locations. It is quite clear that the productivity of wheat, barley and other crops in the NWCZ is highly dependent on the amount and distribution of rainfall as well as the dry spells distribution. Therefore, available water management practices such as supplemental irrigation and water harvesting techniques should be implemented to reduce the potential drought developed for dry spells and to improve the productivity of the cultivated crops.

Geomorphological & Geoarchaeological Indicators of the Holocene Sea-Level Changes on Ras El Hekma Area, NW Coast of Egypt

Ras El Hekma area is a part of the NW coast of Egypt. It is located on the Egyptian Mediterranean Coast, approximately 220 km West of Alexandria City. It is shaped as a triangle with its headland extending into the Mediterranean sea for about 15 km, and is occupied by sedimentary rocks belonging to the Tertiary and Quaternary Eras. Its western coastline consists of Pleistocene Oolitic limestone ridges with separated steep scarps, while the eastern coastline consists of sandy beaches, coastal spits, coastal bars, tombolos and bays.The objective of this paper is to define some geomorphological and geoarchaelological indicators of The Holocene sea-level changes in the study area, especially the geomorphic landforms such as: marine notches, cliffs, sea caves and benches. This is to add to some archaeological remains that have been discovered by the paper's author under the current sea level. These remains include: submerged ruins of Greek and Roman harbors, wells and fish tanks near the coastline (Leuke Akte, Hermaea, Phoinikous and Zygris), in addition to an ancient Roman harbor used during the World War II in Tell El Zaytun area (Site #6). Evaluations of the discovered archaeological remains help our understanding of the evolution of the sea level during the Holocene. This study is based on observation of the relative sea-level curves drawn of the Holocene, detailed geomorphological and Geoarchaelogical surveying, sampling, dating and mapping as well as satellite image interpretation and GIS techniques.

EVALUATION OF DIRECT AND MATERNAL (CO) VARIANCE COMPONENTS AND HERITABILITIES FOR SOME BODY WEIGHTS AND GROWTH TRAITS IN BARKI SHEEP

ABSTRACTThe present study was conducted to investigate the importance of maternal effects on somebody weights and growth traits in Barki sheep. Body weight records and pedigree information of3189 lambs progenies of 186 sires were taken from the Barki sheep flock of the Desert ResearchCentre maintained at two research stations; Ras Elhekma (from 1963 to 1972) and Maryout (from1973 to 2004). The present study dealt with body weights at birth, BW, weaning, 120 days, WWand yearling, 360 days, YW as well as average daily gain from birth to weaning, DGBW and fromweaning to yearling, DGWY. (Co) variance components and the corresponding genetic parameterswere estimated by fitting a series of six animal models using the MTDFREML program. Thesemodels included the significant fixed effects together with the animal, sire and dam as randomeffects. Such models were fitted for each studied trait and differed in ignoring or including variousrandom effects. Log-likelihood ratio tests were conducted to determine the most suitable model forthe studied traits.Results indicated that the animal model which includes only direct genetic effect was the mostappropriate one. Direct heritability estimates ranged from 0.10 to 0.36 for BW, 0.13 to 0.30 for WW,0.07 to 0.23 for YW, 0.13 to 0.26 for DGBW and 0.08 to 0.10 for DGWY. The corresponding valuesfor maternal heritability ranged from 0.18 to 0.20, 0.12 to 0.19, 0.12 to 0.19, 0.10 to 0.17 and 0.01to 0.07, respectively. It is obvious that maternal influences were generally higher for BW, WW andYW than the respective direct ones. The direct and maternal environmental components tended toincrease as age advanced from birth to yearling. The correlation between direct and maternalgenetic effect ranged from 0.07 to 0.35 for the studied traits except for DGWY (-0.72). Althoughtotal direct components has a major contribution (82%) to the phenotypic variance, total maternalcomponents controls the remainder of about 20% and being relatively constant at that level to theyearling stage which imply the importance of maternal influences on growth traits of Barki sheep.The impact of maternal effects on BW appeared to be mainly genetic and tended to decline as ageadvanced. The current investigation advocates that selection process should account for both directand maternal genetic effects to increase the accuracy of genetic evaluation and enhance the geneticgain for growth traits in Barki sheep.

GENETIC, PHENOTYPIC AND ENVIRONMENTAL TRENDS TOWARDS IMPROVING BODY WEIGHT IN BARKI SHEEP

ABSTRACTGenetic, phenotypic and environmental trends for some body weights at birth (BW), 120 days (W120), 360 days (W360) and at 480 days (W480) were estimated to evaluate the breeding plan implemented in Barki sheep flock of the Desert Research Centre. The study also investigated the effects of various environmental factors on these traits. The data set employed in this study was obtained from 3192 records of lambs progenies of 186 sires reared at two research stations; Ras Elhekma (from 1963 to 1972) and Maryout (from 1973 to 2004). Animal breeding values, heritabilities and both genetic and phenotypic correlations for studied body weights were also estimated. Genetic and phenotypic trends were calculated by regression of breeding and phenotypic values on birth year respectively. Environmental trend was attained by subtracting genetic trend from the phenotypic one. Results indicated that average least square means of males had significantly heavier body weights compared with females for the studied body weights. As age of dam increased, body weights tended to be significantly heavier for BW and W120. Ras Elhekma research station exhibited heavier BW, W120 and W360 as well as lighter W480 compared with Maryout research station. The heritabilities of the studied body weights tend to increase as age increased. Genetic correlations among W120, W360 and W480 were greater with higher magnitude than those of phenotypic ones. Least squares means of animal breeding values for birth year were found to range from 3.50 kg to 3.68 kg, from 17.19 kg to 20.24 kg, from 30.46 kg to 37.27 kg and from 35.26 kg to 43.08 kg for BW, W120, W360 and W480, respectively during the examined study period. Genetic, phenotypic and environmental trends for the studied traits exhibited substantial irregular fluctuations among the examined years and being of higher magnitude in Ras Elhekma than in Maryout research station. Ras Elhekma research station had obviously positive genetic trend for BW (15 gm/ year), W120 (189 gm/year), W360 (448 gm/ year) and W480 (521 gm/ year) as well as negative phenotypic trend for BW (-18 gm/ year), W120 (-702 gm/year), W360 (-322 gm/year) and W480 (-345 gm/ year). Positive genetic trends appeared in Ras Elhekma research station indicate genetic improvement in Barki sheep flock reared in this location. The declines in the studied phenotypic traits observed in the Barki sheep flock during the examined period might be attributed to the negative and higher magnitudes of the environmental trends which might reflect some environmental inadequacies such as diseases, insufficient feeding and harsh climatic conditions.

An integrated approach for groundwater assessment at the Northwestern Coast of Egypt (Ras El Hekma area): case study

Ras El Hekma area was chosen for the present study due to its special conditions; the area lacks water for human and agriculture proposes. This area represents one of the main headlands along the southern Mediterranean coast, where population growth and agricultural activities require the corresponding development of groundwater. The main objective of this paper is to monitor and record data about the current groundwater as well as to have a systematic understanding of the hydrogeological setting in the area of study. Also, one of the study objectives is to identify and assess the factors which affect the groundwater occurrence and quality. This assessment will contribute to groundwater protection. The study area has three aquifers: Holocene, Pleistocene, and Middle Miocene aquifers. The recharge to these aquifers comes from the direct infiltration of rainfall and from the surface runoff. Rock–water interaction and the effect of solution and leaching processes on the mineralization of groundwater are studied using the PHREEQC model. Seawater intrusion contributes effectively to the increase in water salinity. The present study clarifies the relationship between the depth to water, the sea level and salinity of water. The groundwater in the area of study is evaluated for drinking, domestic, livestock and agricultural purposes. The present study suggests some recommendations for developing the groundwater in the study area.

Integrated remote sensing and GIS for surface water development. Case study: Ras El Hekma area, northwestern coast of Egypt

The surface water development can help to address the growing demand for water resources and the effects of stormwater flooding on the local environment. The study area was chosen according to its special conditions where it represents one of the main headlands along the southern Mediterranean coast and receives amount of rainfall during the winter season. The main objective of this paper is to monitor and record data about the current surface water status as well as to have a systematic understanding of the water resources base in the study area, and this assessment will contribute in the exploitation of the surface water. The current research is integration between geomorphology, geology, remote sensing, and the applications of geographical information system. The total amount of annual rainfall and surface runoff are estimated (annual rainfall is 23.345 million m3 and surface runoff is 1.167 million m3). On the other hand, the surface runoff which has been resulted from one event (storm) is also estimated to be 483,000 m3/day. The present study introduce some recommendations; the cisterns should be established in the vicinities of the watersheds and on the downstream of the drainage basins to store water before draining to the sea, the dug should be in oolitic limestone to reduce drilling costs, the water reservoirs should be established to store large amount of surface water (from 2,000 to 3,000 m3). Dams are necessary to protect the agriculture activities from any flash hazard which is expected any time.

Application of 2D imaging earth resistivity method for determining the hydrogeological conditions of the coastal area between Marsa Matruh and Ras El Hekma, Mediterranean Sea-Coast, Egypt

Application of 2D imaging earth resistivity method for determining the hydrogeological conditions of the coastal area between Marsa Matruh and Ras El Hekma, Mediterranean Sea-Coast, Egypt