Jizan is one of the Saudi Arabian coastal cities endowed with diverse natural settings, which inc... more Jizan is one of the Saudi Arabian coastal cities endowed with diverse natural settings, which includes Ash Shuqayq in the north, Turfah in the centre and Jizan in the South. This work analysed specific environmental characteristics, such as spits, sabkhas and wadis. Assessments used Landsat imagery to examine coastal change between 1973 and 2011. The cumulative temporal change identified regression trends given by coefficients of determination that explained a significant percentage of data variation for Jizan (R² = 69%) and Turfah (R² = 72%), while Ash Shuqayq was insignificant (R² = 14%). Inter-survey results predicted future change, although trends were not significant, i.e. Jizan (R² = 22%), Turfah (R² = 14%) and Ash Shuqayq (R² = 3 and 61% with outlying value removed). Aerial photos showed regional coastal changes, which included a maximum accretion of 36.4 m and maximum erosion of 12.9 m. These are scientifically effective techniques to monitor regional coastal change, i.e. erosion and accretion and identified rates of 0.59, 1.80 and 3.53 myr⁻¹ for Ash Shuqayq, Turfah and Jizan. Changes were linked to infrastructure developments, e.g. tourism, port development and natural causes, e.g. spit formations and wadi outfalls.
A lack of understanding exists of the origin and textural characteristics of Saudi Arabian Red Se... more A lack of understanding exists of the origin and textural characteristics of Saudi Arabian Red Sea coastal sediments. This paper concerns the southern coastline of Jizan on the Saudi Red Sea. It is some 160 km long characterised by either narrow rocky headlands with intermittent pocket beaches or wide low-lying beaches dissected by wadis. Granulometric testing of samples from 135 locations showed that beach sand size was mainly very fine to medium grained (Mz = 3.93 Ø), sorting ranged from 1.65 to 0.41 and skewness values from −051 to 0.39, being mainly negative; dune sands were medium to fine grained (Mz = 1.13 Ø; average sorting 2.8), while skewness variations within dune samples indicated symmetrical to fine skewed values (бΙ = 0.55 to 0.89). Most foreshore samples were derived from wadis. Wadi mud levels can be high, e.g. Baysh (84%), and wadi Samrah (90%) with mean grain size ranging from very fine to medium sand (Mz = 3.9 Ø), sorting being well to poor (0.45 to 1.52) due to sediment influxes. Sabkha had a wide range of sand/mud and significantly higher carbonate percentages than other environments. Sediment source differences and littoral reworking contributed to grain size variation. The carbonate content varied between 1.5 and 31.5% due to hinterland contributions, and spatial analysis showed increasing quantities of carbonate minerals towards the south. On the wider geographical front, findings from Jizan are similar to those of the Northern United Arab Emirates (UAE), including sabkhas, being composed of sand, skeletal carbonate, fine fluvial material and wind-blown silt and clay components of wadi origin. Further work on the northeastern Red Sea edge can hopefully confirm these findings.
Forty-five beaches at 41 bathing area locations in Wales were analysed for litter in 2000 and 201... more Forty-five beaches at 41 bathing area locations in Wales were analysed for litter in 2000 and 2012, via a standard seven category checklist. Fourteen resorts, 2 urban, 11 village, 15 rural 3 remote, were graded, A to D. A grade beach numbers changed from 5 to19; B, 27 to 24; C, 9 to 2; D, 4 to 0, many beaches maintaining their current status. Assuming trend continuance within the next 12 years, the A:B grade ratio would approach equilibrium of 44:56, with no grade C or D beaches. Recreational litter was ubiquitous; fishing materials prevalent along Cardigan Bay. New water treatment plant investment reduced sewage related debris. Despite apparent increased awareness of beach litter, improving visitor behaviour through information/education should be a future priority. Removing a few gross items could improve beach grades at little cost to local authorities and benefits to the Welsh economy.
The sixth international conference on the Red Sea region.
"The Al-Kharrar lagoon is ~17 km long with an average width of 3.5 km, and connected to the Red S... more "The Al-Kharrar lagoon is ~17 km long with an average width of 3.5 km, and connected to the Red Sea through a narrow channel ~250 m wide. The fringes of the lagoon are bounded by inter-tidal flats and sabkhas that extend ~3 km inland from the waterline. At some places, elevated sandy berms separate the sabkhas from the lagoon where the low-lying areas are occasionally covered with a thin sheet of water.The lagoon is mostly covered with fine sediments (mud to sandy mud), except at the entrance, where coars- er sediments (sand to gravelly sand) dominate. Mangrove (Avicennia marina) stands are scattered around the islands in the centre of the lagoon that trap finer sediments, and various species of coral are common in the lagoon. The northerly and north west- erly winds influence the movement of water and fine sediments in the lagoon to the adjacent sabkhas in the south, particularly during spring tides. Strong tidal currents up to 1m s-1 prevail at the entrance of the lagoon, and control the bathymetry, particularly at the mouth, as well as the winnowing of the fine sediments and their transportation to the margins where they settle down forming levee-like structures.
Fluvial materials are transported into the lagoon by the wadis during sporadic rainfall, and frequent dust storms contribute a significant quantity of quartz. Two sedimentary environments and sources have been recognized based on the dispersal pattern and sediment make-up: 1) the finer terrigenous environment, and 2) the coarser biogenic environment. The mineralogical composition of the bottom sediments is relatively uni- form, whereas the minor variation in the mineralogical make-up is caused by mixing from the local igneous-metamorphic source rocks and the environment of deposition.
However, a third but a minor source is also observed - the evaporite deposits from the adjoining sabkhas. The clay minerals are derived from the wadis during flash floods and are possibly transported by the wind. The sediments are also stained gray-black be- cause of a reducing environment, especially close to the mangrove stands. The total or- ganic carbon has a positive correlation with the sediment texture and sediment colour, that is, in finer and dark coloured sediments, where the total organic carbon is higher because finer sediment preserves organic matter well. The sources of total organic carbon are the organic debris. The process of flocculation has been observed, especially in the south by the occasional mixing of fresh and saline water.
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Jizan is one of the Saudi Arabian coastal cities endowed with diverse natural settings, which inc... more Jizan is one of the Saudi Arabian coastal cities endowed with diverse natural settings, which includes Ash Shuqayq in the north, Turfah in the centre and Jizan in the South. This work analysed specific environmental characteristics, such as spits, sabkhas and wadis. Assessments used Landsat imagery to examine coastal change between 1973 and 2011. The cumulative temporal change identified regression trends given by coefficients of determination that explained a significant percentage of data variation for Jizan (R² = 69%) and Turfah (R² = 72%), while Ash Shuqayq was insignificant (R² = 14%). Inter-survey results predicted future change, although trends were not significant, i.e. Jizan (R² = 22%), Turfah (R² = 14%) and Ash Shuqayq (R² = 3 and 61% with outlying value removed). Aerial photos showed regional coastal changes, which included a maximum accretion of 36.4 m and maximum erosion of 12.9 m. These are scientifically effective techniques to monitor regional coastal change, i.e. erosion and accretion and identified rates of 0.59, 1.80 and 3.53 myr⁻¹ for Ash Shuqayq, Turfah and Jizan. Changes were linked to infrastructure developments, e.g. tourism, port development and natural causes, e.g. spit formations and wadi outfalls.
A lack of understanding exists of the origin and textural characteristics of Saudi Arabian Red Se... more A lack of understanding exists of the origin and textural characteristics of Saudi Arabian Red Sea coastal sediments. This paper concerns the southern coastline of Jizan on the Saudi Red Sea. It is some 160 km long characterised by either narrow rocky headlands with intermittent pocket beaches or wide low-lying beaches dissected by wadis. Granulometric testing of samples from 135 locations showed that beach sand size was mainly very fine to medium grained (Mz = 3.93 Ø), sorting ranged from 1.65 to 0.41 and skewness values from −051 to 0.39, being mainly negative; dune sands were medium to fine grained (Mz = 1.13 Ø; average sorting 2.8), while skewness variations within dune samples indicated symmetrical to fine skewed values (бΙ = 0.55 to 0.89). Most foreshore samples were derived from wadis. Wadi mud levels can be high, e.g. Baysh (84%), and wadi Samrah (90%) with mean grain size ranging from very fine to medium sand (Mz = 3.9 Ø), sorting being well to poor (0.45 to 1.52) due to sediment influxes. Sabkha had a wide range of sand/mud and significantly higher carbonate percentages than other environments. Sediment source differences and littoral reworking contributed to grain size variation. The carbonate content varied between 1.5 and 31.5% due to hinterland contributions, and spatial analysis showed increasing quantities of carbonate minerals towards the south. On the wider geographical front, findings from Jizan are similar to those of the Northern United Arab Emirates (UAE), including sabkhas, being composed of sand, skeletal carbonate, fine fluvial material and wind-blown silt and clay components of wadi origin. Further work on the northeastern Red Sea edge can hopefully confirm these findings.
Forty-five beaches at 41 bathing area locations in Wales were analysed for litter in 2000 and 201... more Forty-five beaches at 41 bathing area locations in Wales were analysed for litter in 2000 and 2012, via a standard seven category checklist. Fourteen resorts, 2 urban, 11 village, 15 rural 3 remote, were graded, A to D. A grade beach numbers changed from 5 to19; B, 27 to 24; C, 9 to 2; D, 4 to 0, many beaches maintaining their current status. Assuming trend continuance within the next 12 years, the A:B grade ratio would approach equilibrium of 44:56, with no grade C or D beaches. Recreational litter was ubiquitous; fishing materials prevalent along Cardigan Bay. New water treatment plant investment reduced sewage related debris. Despite apparent increased awareness of beach litter, improving visitor behaviour through information/education should be a future priority. Removing a few gross items could improve beach grades at little cost to local authorities and benefits to the Welsh economy.
The sixth international conference on the Red Sea region.
"The Al-Kharrar lagoon is ~17 km long with an average width of 3.5 km, and connected to the Red S... more "The Al-Kharrar lagoon is ~17 km long with an average width of 3.5 km, and connected to the Red Sea through a narrow channel ~250 m wide. The fringes of the lagoon are bounded by inter-tidal flats and sabkhas that extend ~3 km inland from the waterline. At some places, elevated sandy berms separate the sabkhas from the lagoon where the low-lying areas are occasionally covered with a thin sheet of water.The lagoon is mostly covered with fine sediments (mud to sandy mud), except at the entrance, where coars- er sediments (sand to gravelly sand) dominate. Mangrove (Avicennia marina) stands are scattered around the islands in the centre of the lagoon that trap finer sediments, and various species of coral are common in the lagoon. The northerly and north west- erly winds influence the movement of water and fine sediments in the lagoon to the adjacent sabkhas in the south, particularly during spring tides. Strong tidal currents up to 1m s-1 prevail at the entrance of the lagoon, and control the bathymetry, particularly at the mouth, as well as the winnowing of the fine sediments and their transportation to the margins where they settle down forming levee-like structures.
Fluvial materials are transported into the lagoon by the wadis during sporadic rainfall, and frequent dust storms contribute a significant quantity of quartz. Two sedimentary environments and sources have been recognized based on the dispersal pattern and sediment make-up: 1) the finer terrigenous environment, and 2) the coarser biogenic environment. The mineralogical composition of the bottom sediments is relatively uni- form, whereas the minor variation in the mineralogical make-up is caused by mixing from the local igneous-metamorphic source rocks and the environment of deposition.
However, a third but a minor source is also observed - the evaporite deposits from the adjoining sabkhas. The clay minerals are derived from the wadis during flash floods and are possibly transported by the wind. The sediments are also stained gray-black be- cause of a reducing environment, especially close to the mangrove stands. The total or- ganic carbon has a positive correlation with the sediment texture and sediment colour, that is, in finer and dark coloured sediments, where the total organic carbon is higher because finer sediment preserves organic matter well. The sources of total organic carbon are the organic debris. The process of flocculation has been observed, especially in the south by the occasional mixing of fresh and saline water.
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Papers by Omar Alharbi
Fluvial materials are transported into the lagoon by the wadis during sporadic rainfall, and frequent dust storms contribute a significant quantity of quartz. Two sedimentary environments and sources have been recognized based on the dispersal pattern and sediment make-up: 1) the finer terrigenous environment, and 2) the coarser biogenic environment. The mineralogical composition of the bottom sediments is relatively uni- form, whereas the minor variation in the mineralogical make-up is caused by mixing from the local igneous-metamorphic source rocks and the environment of deposition.
However, a third but a minor source is also observed - the evaporite deposits from the adjoining sabkhas. The clay minerals are derived from the wadis during flash floods and are possibly transported by the wind. The sediments are also stained gray-black be- cause of a reducing environment, especially close to the mangrove stands. The total or- ganic carbon has a positive correlation with the sediment texture and sediment colour, that is, in finer and dark coloured sediments, where the total organic carbon is higher because finer sediment preserves organic matter well. The sources of total organic carbon are the organic debris. The process of flocculation has been observed, especially in the south by the occasional mixing of fresh and saline water.
"
Fluvial materials are transported into the lagoon by the wadis during sporadic rainfall, and frequent dust storms contribute a significant quantity of quartz. Two sedimentary environments and sources have been recognized based on the dispersal pattern and sediment make-up: 1) the finer terrigenous environment, and 2) the coarser biogenic environment. The mineralogical composition of the bottom sediments is relatively uni- form, whereas the minor variation in the mineralogical make-up is caused by mixing from the local igneous-metamorphic source rocks and the environment of deposition.
However, a third but a minor source is also observed - the evaporite deposits from the adjoining sabkhas. The clay minerals are derived from the wadis during flash floods and are possibly transported by the wind. The sediments are also stained gray-black be- cause of a reducing environment, especially close to the mangrove stands. The total or- ganic carbon has a positive correlation with the sediment texture and sediment colour, that is, in finer and dark coloured sediments, where the total organic carbon is higher because finer sediment preserves organic matter well. The sources of total organic carbon are the organic debris. The process of flocculation has been observed, especially in the south by the occasional mixing of fresh and saline water.
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