Central Coastal Zone Research Articles

Assessment of pollutants in coastal waters, sediments, and biota of marine ecosystems in Algeria, North Africa

This study aims to assess the chemical and ecological quality of the marine ecosystem in Algerian central coastal zone (Bay of Algiers (AB) and Bou-Ismail Bay (BIB)) by examining several quality indicators of the marine ecosystem: water, sediment, and biota. Except for stations near the mouths of wadis and industrial and urban discharges released without prior treatment, the study of the physicochemical water quality in the different sampling stations revealed a more or less normal variation in temperature and salinity. According to nutrient salt analysis, all studied stations (in AB and BIB) have high nitrogen levels, such as ammonium and nitrate. However, low levels of phosphate were detected, indicating that this element is scarce in the Algerian coastal marine waters. Three trace metals were also analyzed in the sediments of both bays. Pb ranged from 21.15 to 52.69 μg g–1 dry weight (dw), Zn from 19.32 to 175.1 μg g–1 dw and Cd between 0.87 and 2.031 μg g–1 dw. Contamination factors ranged from 0.62 to 1.55 for Pb, 0.2 to 1.85 for Zn and 1.74 to 4.04 for Cd. Analysis of these three metals in sediment samples reveals their presence at most stations studied. The contamination index calculation shows a moderate anthropogenic intake that requires continuous monitoring to protect the study area’s ecosystem. Crucially, the analysis of fish products revealed a lack of chemical risk concerning trace metals, known for their detrimental health effects. However, this conclusion does not dismiss the potential for subtle contamination, warranting persistent environmental surveillance. Consequently, sustained efforts in environmental monitoring are imperative to ensure the preservation of the marine ecosystem amidst escalating anthropogenic pressures.

Environmental Controls of phytoplankton in the river dominated sub-tropical coastal ecosystem of Bangladesh

Sub-tropical coastal ecosystems are considered as the hotspot of species diversity. However, due to challenges regarding data collection, these regions are inherently data-limited and thus hindering informed species conservation strategies. Considering this, the present study aimed to assess the ecological characteristics of a river dominated sub-tropical coastal ecosystem of Bangladesh. More specifically, in this study we examined the spatial variability in environmental conditions and phytoplankton in the coastal ecosystems of Bangladesh. We also examined the causal relationship between environmental variables and phytoplankton species abundance. Data on environmental variables, including temperature, salinity, dissolved oxygen, turbidity, and macronutrients, was gathered in the north-east monsoon season between 2020 and 2022. We performed multivariate statistics to identify the variability in phytoplankton community dynamics. Results showed strong spatial variability in environmental conditions. Salinity, turbidity, nutrients concentrations and chlorophyll were found as the major drivers of this spatial heterogeneity. Central coast was characterized by low salinity, and high turbidity and silicate concentration while south-east coast was characterized by high salinity and low nutrient concentrations. In contrast, the south-west coast was characterized by high nitrate and phosphate, and moderate level of turbidity and salinity. Furthermore, our study identified 121 phytoplankton species. Maximum species diversity was observed in the south-west coast followed by central and south-east coast. Whereas 66 species occurred simultaneously in the three coastal zones, Coscinodiscus, Odontella and Nitzchia were the dominant phytoplankton genus in the central coastal zone. Skeletonema, Ditylum and Proboscia were found as dominant species in the south-east coastal zone. Coscinodiscus, Odontella, Nitzchia, Proboscia, Ditylum and Thalassionema were found as the key species in the south-west coastal zone. Seven explanatory variables (i.e. temperature, salinity, turbidity, silicate, nitrite, phosphate and zooplankton abundance) jointly explained about 44% to 73% variability in phytoplankton species abundance. We identified salinity and macronutrients as the major drivers of phytoplankton variability. This study is the first systematic report on phytoplankton community dynamics in-relation to environmental variables considering data from the entire coastal ecosystem of Bangladesh.

Evaluating the long-term geomorphic process in-relation to hydrodynamics in the central coastal zone of Bangladesh

The central coast of Bangladesh is dynamic for its geographical location, hydrodynamic characteristics and residual flow. The research employed the Digital Shoreline Analysis System (DSAS), an ArcGIS extension tool, to conduct a historical trend analysis of shoreline. The study demonstrates that the central coast is eroding to the north and accreting to the south. The highest accretion value was found as 195.42 m/year, whereas the maximum value of erosion was estimated as −185.83 m/year, according to End Point Rate (EPR). The Linear Regression Rate (LRR) indicates that the average rate of erosion and accretion are −17.77 m/year and 17.88 m/year, respectively. Meanwhile, using Weighted Linear Regression (WLR), 0.48% of all transects demonstrated statistically significant erosion, while 0.43% showed statistically significant accretion. During the wet season, heavy river discharge leads to a low salt level in the ocean. Ocean currents hit central coast of Bangladesh from east to west, affecting the majority of the islands in the Meghna Estuary in the dry season. Changes in current directions can be seen during the wet seasons. Southern central coast areas are hit by south-east currents that split in two directions. The Sandwip Channel has a flow of 10,000 to 15,000 m³ s−1 northward. The Tetulia River, Shahbazpur Channel, and Hatia-Sandwip flow southward at rates ranging from 3000 to 17,000 m³ s−1, 14,000 to 60,000 m³ s−1, and 7000 to 39,000 m³ s−1, respectively. In the Meghna Estuary, the combined forces result in a counter-clockwise residual circulation, with the northward flow in the Sandwip channel and southbound flow in the Hatia and Shahbazpur channels. As a result of hydrodynamic, ocean currents, and residual flow, the Central Coast of Bangladesh is continually changing in appearance.

Identification and Economic Potentiality of Mineral Sands Resources of Hatiya Island, Bangladesh

Hatiya is the second largest island of Bangladesh and is situated near the Meghna River estuary in the central coastal zone of Bangladesh. This island hosts a few scenic beaches with a huge deposit of mineral sands. Representative mineral sand samples from various beaches of this island were collected during the year 2019, and analyzed for different mineralogical contents using state-of-the-art techniques, such as WD-XRF, XRD, SEM and EDX. This study determined various mineralogical contents, such as SiO2 (73.58%), micas (40.30%), Al2O3 (12.13%), TiO2 (0.56%), MgO (1.31%), Fe2O3 (4.71%), K2O (3.1%), Na2O (1.92%), CaO (3.16%), some earth metals, and heavy minerals, such as ilmenite (14.77%), garnet (11.02%), rutile (14.94%), magnetite (15.26%), and zircon (13.63%), were identified in the analyzed samples. It is suggested that the studied sand can be utilized as a raw material in the glass industry, due to its high SiO2 content. The approximate prices of heavy and light minerals, such as garnet (USD 75–USD 210/mt), ilmenite (USD 110/mt), magnetite (USD 84/mt), rutile (USD 840/mt), zircon (USD 1050/mt) and micas (USD 109/mt), some oxides such as K2O (USD 350–400/mt), CaO (USD 350–450/mt), Al2O3 (USD 1000-USD 1300/mt), TiO2 (USD 4000–4500/mt), and Fe2O3 (USD 650–1500/mt), and some other heavy metals (Rb, Th, Ba, V, Cr, Cs, Ni and Co), indicates a great economic value of the sand of the Hatiya Island beaches. This study recommends that Hatiya Island’s minerals should be mined responsibly and used effectively, to enhance the nation’s economy.

Impact of Population Growth in the Central Coastal Zone of Chile: Factors for Estimating Tourism Carrying Capacity Based on the Case Study of One Latin American Seaside Resort

El Quisco is a district and popular seaside resort on the coast of Chile that has suffered the effects of the growing demand for second homes and tourism activities. The district has the fourth highest influx of a floating population in the region, which has had numerous impacts on the district at several levels. The objective of this article is to examine the issue of carrying capacity in Chile and its public management at the local level. To this end, this research developed an exploratory and instrumental case study. Carrying capacity problems were first identified in the existing literature. This information was subsequently complemented with more local information by means of: analysis of territorial planning instruments (TPIs) relating to the district; participative workshops with municipal government stakeholders; and, lastly, confirmation of the problems identified through correlation analysis of available historical data. The main result of this research was the determination of carrying capacity issues in El Quisco. This broadly coincides with indications from the existing literature and TPIs, while factors identified by local stakeholders are territory-specific, giving rise to new measurement variables. It was possible, in turn, to rule out certain carrying capacity issues perceived by the community.

Distribution of rare earth elements in surface sediments of the western Sunda Shelf: Constraints from sedimentology and mineralogy

To understand the modern sedimentation and land-sea interaction processes in the Sunda Shelf, we evaluated the rare earth element (REE) compositions, the total organic carbon (TOC) contents, grain sizes, and detrital minerals of 39 surface sediments, collected from the western Sunda Shelf. All of the sampled sediments are characterised by a higher content of light REEs (LREEs) relative to the content of heavy REEs (HREEs) with negative Eu anomalies. The total content of REE (ΣREE) in the sediments ranges from 7 μg/g to 193 μg/g, with an average of 119 μg/g. Due to the uneven spatial distribution of REEs in the study area, a Q-cluster analysis is applied to the mean grain size (Mz), ∑REE, δEu, δCe, (La/Yb)N, and (Gd/Yb)N data. On this basis, the study area can be classified into three geochemical provinces. The north to central zone in the study area is designated as province I, which has the highest REE content among the three provinces. This is a result of the finer grain size, dominance of siderite, and higher TOC contents of the sediments in province I. The REE content of province II in the southwest coastal zone is lower than that of province I due primarily to a coarser grain size and high quartz, biodetritus, and plagioclase contents. Covering the central coastal zone, province III has the lowest REE content among the three provinces because of the extremely coarse grain size and very high quartz and biodetritus contents. The upper continental crust (UCC)-normalised REE patterns differ markedly among the three provinces, thereby indicating different provenances and transport mechanisms. Based on the provenance discrimination plot and the UCC-normalised REE patterns of these three provinces and adjacent rivers, we infer that province I is largely fed by the Mekong and Kelantan rivers. The fine-grained sediments from these rivers are transported to north and central zone by the northeast monsoon current. The Pahang River is identified as the main sediment source of province II. The coarse-grained sediments from this river mostly accumulate near the estuary via hydrodynamic sorting, while finer-grained sediments are transported to the south by the southward coastal currents. The sediments in province III are inferred as being primarily the result of coastal erosion due to the strong wave energy in this area, as well as offshore and longshore sediment transport acting, in parallel to the coast line. Our study can serve as a reference for studying the diffusion and transport processes of mountainous river sediment and the evolution of the paleoclimate and paleoenvironment in tropical low-latitude regions.

Influence of hydro-climatic factors on future coastal land susceptibility to erosion in Bangladesh: a geospatial modelling approach

This study envisaged the likely impacts of future hydro-climatic changes on the susceptibility of coastal land to erosion through the development of raster-based geographical information system (GIS) model called land susceptibility to coastal erosion (LSCE). The model was applied to the coastal area of Bangladesh to assess future erosion susceptibility under four greenhouse gas (GHG) concentration trajectories: A1B, RCP2.6, RCP4.5 and RCP8.5. The results indicate considerable changes in future scenarios of coastal land susceptibility to erosion in the area compared to current baseline conditions. The current area of 276.33 km2 (0.61%) high and very high susceptible lands would be substantially increased to 1019.13 km2 (2.25% of land), 799.16 km2 (1.77%), 1181.38 km2 (2.61%) and 4040.71 km2 (8.96%) by 2080 under A1B, RCP2.6, RCP4.5 and RCP8.5 scenarios, respectively. Spatially, the western and eastern coastal zones would have low to moderate susceptibility to erosion, whereas the central coastal zone would have moderate to high/very high susceptibility to erosion. Seasonally, the model predicted the high erosion susceptibility during the monsoon seasons and very low erosion susceptibility during the winter seasons in the future. The model outputs were enhanced by integrating experts’ judgements through fuzzy cognitive mapping (FCM) approach. The LSCE model might be indispensable for coastal researchers in generating future scenarios of physical susceptibility to erosion for highly dynamic coastal areas around the world.

The Cyclops Mountains Massif (New Guinea, Indonesia) as the provenance area for metal-bearing shelf sediments from the Carolinian Sea

In 2009, on the initiative of PT Halmahera Perkasa the “Jayapura” exploration project was carried out in Indonesia. As part of this project, exploration of the sea bottom in the northern coast of New Guinea was carried out over a distance of ~45 km. The suction dredge collected 59 samples of loose sediments from the shelf bottom surface of the Carolinian Sea (to a depth of 60 m below the sea-floor). The extracted samples are usually poorly and moderately sorted sands (5 samples), medium-grained sands (21 samples), and fine-grained sands (33 samples). The sand composition shows, among others, a wide spectrum of heavy minerals of ultra-mafic (Cr-garnet, chromium spinel, Mg-olivine) and metamorphic (epidote, clinochlore, amphibole, titanite) origin. The content of heavy minerals in the sediments is up to 54.77 wt.%. It was found that the source of heavy fraction in the eastern and western parts of the coast is the rock of the ophiolite series building the Cyclops Mountains Massif. The mineral composition of sediments from the central coastal zone corresponds to the types of rocks building the metamorphic core of the Cyclops Mountains (amphibolite, gneisses, andesite). Three mineral-geochemical subprovinces were determined on the basis of analyses of heavy mineral decomposition and chemical analyses of sediments. Shelf sediment from the eastern part of the coast is characterized by an increased content of strategic metals (Ni up to 3560, W up to 3130 and Co up to 142 ppm). In the central zone, the V content increases up to 244 ppm and the Ag content up to 5 ppm. In the shelf sediments there is a strong depletion in the REE.

The feasibility of high yielding aus-aman-rabi cropping systems in the polders of the low salinity coastal zone of Bangladesh

Cropping intensity and agricultural productivity in the polders of the coastal zone of Bangladesh are much lower than that of most of the country. The main reasons for this are waterlogging, the late harvest (December/January) of the rainy season rice crop (known as ‘aman’), and the lack of readily accessible fresh water during the dry season in the polders. Waterlogging prevents the production of high yielding and earlier maturing rainy season rice varieties (HYV aman), and of high yielding/value rabi (dry season) crops such as maize and sunflower. However, gravity drainage of excess water from the polders is physically feasible. Furthermore, the rivers surrounding the polders in the central coastal zone (Barisal Division) contain large volumes of fresh river water throughout the year. Research was therefore undertaken to evaluate, under good water management, the feasibility of intensifying to high yielding rice-rice-rabi cropping systems in the low salinity central coastal zone. A replicated cropping system experiment was conducted for two years at Patuakhali using a short duration modern ‘aus’ variety (aus is the name of the rice crop grown during the early rainy season) (BRRI dhan65), a medium duration modern aman variety (BRRI dhan44), and high yielding/value rabi crops. The cropping systems included four aus sowing dates (20 March, 5 and 20 April, 5 May) which resulted in four aman and four rabi sowing dates. Two rabi crops were compared within each sowing date (maize – Pacific 984, sunflower – Hysun 33). Annual cropping system rice equivalent yield (REY) ranged from 13.7 to 20.0 t/ha. All systems were profitable with 100% of labour purchased, although benefit cost ratios (BCR) were not always >3, suggesting low attractiveness to farmers. However, most polder farms are small, with 30–60% of labour provided by the family. With 75% or less of labour purchased (the rest provided by family), all cropping systems were financially attractive, even with a 10% decline in grain price. Rabi crop yield was the main determinant of total system REY and profitability, both of which declined as sowing date of the rabi crops was delayed beyond 15 December. Optimisation of sowing date of the rabi crops should therefore be the first consideration in cropping system intensification for the low salinity coastal zone. The optimum sowing date of both the maize and sunflower was mid-December. For adequate "turn around" time between all crops, for the varieties used in this study, the aus crop should be sown in mid-April and the aman crop in mid-August. This research shows that, with good water management, it is possible to implement highly productive and profitable aus-aman-rabi cropping systems in the low salinity coastal zone of Bangladesh.

Variability of Nutrients in Seawater of Coastal Zone from Khanh Hoa to Bac Lieu

This paper is based on data from two surveys (October 2013 and May 2015) on the coastal zone from Khanh Hoa to Bac Lieu and the data from 1992 until now. Results indicated that in southwest monsoon period, the variations of nutrient concentrations in South Central coastal zone of Vietnam were not clearly, except higher concentration of phosphate in the period 1992-1994 and the 2006, 2015 and higher concentration of silicate in the 2006, 2015. In the northeast monsoon period, the highest concentration of phosphate and silicate were recorded in October 2013. In the Southeast coastal zone of Vietnam, the concentration of nutrients (nitrate and silicate) tend to increase in both monsoon periods in shallow area (less than 30 m of depth). But the variations of nutrients concentration were not clearly or few in deeper area (over 30 m of depth).

Combined top-down and bottom-up climate change impact assessment for the hydrological system in the Vu Gia- Thu Bon River Basin

Vu Gia- Thu Bon (VGTB) River Basin, located in the Central Coastal zone of Viet Nam currently faces water shortage. Climate change is expected to exacerbate the challenge. Therefore, there is a need to study the impacts of climate change on water shortage in the river basin. The study adopts a combined top-down and bottom-up climate change impact assessment to address the impacts of climate change on water shortage in the VGTB River Basin. A MIKE BASIN water balance model for the river basin was established to simulate the response of the hydrological system. Simulations were performed through parametrically varying temperature and precipitation to determine the vulnerability space of water shortage. General Circulation Models (GCMs) were then utilized to provide climate projections for the river basin. The output from GCMs was then mapped onto the vulnerability space determined earlier. In total, 9 out of 55 water demand nodes in the simulation are expected to face problematic conditions as future climate changes.

Analysis of the influence of ENSO phenomena on wave climate on the central coastal zone of Rio de Janeiro (Brazil)

This paper evaluates the influence of the El Nino - Southern Oscillation on the wave climate variability in the central region of Rio de Janeiro's coastal zone. The regional climate of the area was characterized using the WAVEWATCH III wave data model, obtained from NOAA, organized as a 35 year time series (1979-2013). These data were validated for the study area and a characterization and analysis performed by focusing on years with occurrence of strong El Nino/La Nina events. The correla- tion between the interannual variability of significant wave height and Oceanic Nino Index showed a slight reduction in sig- nificant wave height during El Nino years and the opposite pattern during La Nina years, with a lag of four months. This de- crease could be attributed to the intensification of the South Atlantic High with a corresponding increase in the occurrence of subtropical jets during periods of El Nino. This weather change causes the blocking of cold fronts in the southern region of Brazil and the consequent reduction in the percentage of waves from the south along the southeast coast.

Trace elements in Anadara spp. (Mollusca: Bivalva) collected along the coast of Vietnam, with emphasis on regional differences and human health risk assessment

This study measured concentrations of 21 trace elements in whole soft tissue of the blood cockle Anadara spp., which is a common food for local people, collected along the coast of Vietnam. Results showed that concentrations of As, Sr, Mo, Sn, and Pb in cockles collected from Khanh Hoa Province in the Central Coastal Zone (CCZ) had higher values than those from the other regions, while cockles collected from the Mekong River Delta (MRD) showed the highest concentrations of Hg. Regional differences in trace element concentrations of the cockle may be due to differences in human activities, i.e., shipyards in the CCZ and agriculture in the MRD. Trace element concentrations measured in the soft tissues of blood cockles investigated here were within safe levels for human consumption following criteria by the European Commission (EC) and the United States Food and Drug Agency, but several specimens had Cd levels exceeding the EC guidelines of 1 μg/g wet weight. The estimated target hazard quotients for trace elements via consuming bivalves were <1, indicating that the cumulative noncarcinogenic risk was completely insignificant. However, the estimated target cancer risk values by assumed inorganic As concentrations seem to implicate consumption of these cockles as posing potential human health concerns.

Concentrations of trace elements in Meretrix spp. (Mollusca: Bivalva) along the coasts of Vietnam

The dominant coastal bivalve in Vietnam, hard clams Meretrix spp., collected from the South Key Economic Zone (SKEZ), the Mekong River Delta, and the Central Coastal Zone (CCZ) were analyzed for 21 trace elements. Comparison of the results from the three regions indicated that levels of most of the trace elements, especially As, Mo, Sn, and Pb, were highest in the samples collected from the CCZ, whereas most of the trace elements were found to be present at relatively low levels in samples from the SKEZ. The high concentrations of these trace elements in the CCZ, a sparsely populated region with less human activity than the other two regions, were believed to have originated from industrial waste produced in a shipyard. Although the trace element concentrations in the bivalves were within safe levels for human-consumption criteria reported by the United State Food and Drug Administration and the European Commission, estimation of cancer risk based on As concentration indicates that the hard clams from the CCZ pose a high risk to consumers. Thus, the industrial waste produced in the less densely populated region might increase the health risk to consumers via the contamination of bivalves commonly used as food.

A combinated approach to investigate the biochemistry and hydrography of a shallow bay in the South Adriatic Sea: the Gulf of Manfredonia (Italy)

The main goal of this study is to understand the hydrological and biochemical set up and processes of a marine coastal area located in the western side of the south Adriatic sea (the gulf of Manfredonia) by the use of both satellite images and in situ investigations A water sampling in the gulf of Manfredonia was performed at 18 fixed stations in June 2003; physico-chemical and biological parameters (temperature, salinity, dissolved oxygen and fluorescence) were measured along the water column and water samples were collected to analyse dissolved nutrients (ammonia, nitrite, nitrate, phosphate and silicate), total nutrients (nitrogen and phosphorus), chlorophyll a and total suspended solids. Surface spatial distributions of field collected data were examined to characterize biochemical and hydrographic conditions of the Gulf of Manfredonia and these results were related with the remote sensing analysis data. Remote sensed data (obtained by Landsat 7 TM and Modis Terra) were processed to obtain maps of chlorophyll a, temperature and optical characteristics of the gulf; these maps were compared to in situ data. From physico-chemical measurements no stratification was observed in the water column except for the south-eastern area. High concentrations of silicate and ammonia were observed in the northern zone of the gulf, while nitrate, phosphate, chlorophyll a and total suspended solids distributions showed higher values in the central coastal zone. These results were confirmed by remote sensing analysis; Modis elaboration showed a distribution with higher concentrations of chlorophyll a near the coast and Landsat images highlighted the extension of the surrounding agricultural areas crossed by the two main rivers which discharge into the gulf. The integration between field data with the remote sensing analysis showed to be a valid support in coastal zone management.

Sediment transport and budget of the central coastal zone of Holland

Based on the available short-term morphological data (1964–1992), the net yearly-averaged sand volume change in the surfzone ( 3 −8 m NAP; to local datum approximately mean sea level) along the coast of Holland was found to be 125,000 m 3 year (sedimentation), including beach nourishments. A sand budget model has been developed, which describes the sand volume change (in m 3 year ) in each compartment of the coastal area given known gradients of the computed longshore and cross-shore transport rates and known source/sink terms (nourishment, dumping and dredging). The model area extends in cross-shore direction from the +3 m NAP contour to the −20 m NAP contour. The sand budget model has been calibrated (hindcast study) using the yearly-averaged sand volume changes derived from bathymetry data (Jarkus-data base) collected during the period 1964–1992. Input data are the gradients of the yearly-averaged longshore and cross-shore transport rates at the boundaries of the compartments and the available data of beach nourishment, dumping and dredging in the same period. A 2DV-mathematical model representing the hydrodynamic (waves and currents) and sand transport processes in a cross-shore profile was applied to compute the yearly-averaged transport rates in various profiles along the coast at depths of 20 and 8 m and in the surf zone. A detailed sensitivity study was performed to determine the variation ranges of the transport rates.

Structuring the Late Stone Age of Southeastern Arabia

This paper treats the classification of a number of facies in the Late Stone Age of Southeastern Arabia. The basis for this classification is a selection of substantial find complexes of chipped stone artifacts from sites located along the coast of Oman. Human occupation in the region dates to the beginning of the Holocene, but insufficient material is available for the first quarter of the post‐Pleistocene era. At the beginning of the second quarter of the Holocene, we find a relatively undifferentiated stone tool‐using facies (Wadi‐Wutayya‐Facies) which was appar‐ ently contemporary with the Qatar B blade‐arrowhead horizon in the interior of the Oman peninsula. Early in the 5th millennium BC, the Wadi‐Wutayya‐Facies was superseded by the Saruq‐Facies which can be seen as a local variant of the “Arabian bifacial tradition”. The high point in the Late Stone Age occupation of the coast was reached early in the 4th millennium BC when various local facies can be distinguished. These include the Ra's‐al‐Hamra‐Facies in the central coastal zone around Muscat and the Bir‐Bira‐Facies in the area around Sur. This phase, which was characterized particularly by the formation of shell middens, seems to have lasted only about 500 years. An essentially aceramic occupation on the coast of the Gulf of Oman, called the Bandar‐Jissa‐Facies, represents the final phase in the classification of Late Stone Age occupation outlined here. This facies was characterized by the use of a simple stone tool industry alongside of metal artifacts, and was contemporary with the Early Bronze age occupation of the southern and southwestern flanks of the Oman mountains. Information on categories of finds other than chipped stone, particularly those made of groundstone and shell, as well as observations on the economic and environmental history of the periods discussed, complement the study of the stone tool industries and form the basis for an outline of the history of Southeastern Arabia in the second quarter of the post‐glacial era.

Planning and management of the coastal zone in India—a perspective

Abstract India's coastal zone has, since ancient times, played a very significant role in socioeconomic, political, and defense developments. For a developing country like India with a vast coastal zone, there is a need for establishing one Central Coastal Zone Management Authority at the national level and a suitable agency in each of the maritime states for properly coordinating and implementing the coastal zone management program of the country. It is necessary to consider all major uses of the coastal zone, relevant to its physical, chemical, and biological regimes, as well as man's socioeconomic and political systems. The goals must be clearly specified and policies with necessary built‐in legislative powers should be framed for implementation. Most recent advances in ocean science and technology are to be used to resolve any conflict that may arise in the interactive uses of the coastal zone and implementation of public goals. Engineering and management techniques should be evolved and applied in pl...

Les Plans de répartition de la population en Israël

Planning of spatial distribution of population in Israël (Abstract). — The problem of an optimum spatial distribution of population — a theoretical issue for the most countries— became a very practical problem for Israël which more than trebled its population since 1948, mostly by immigration. At the commencement of the Israeli State, — 1948 about 10 p. 100 of the total Jewich population of the country was concentrated within Tel-Aviv, Haifa and Jérusalem Metropolitan areas and about 80 p. 100 within the Central Coastal zone. The planned policy since 1948 aimedat réduction of population concentration in Coastal zone and tried to create an hierar-chical pattern of rural and régional urban centres. Country-wide plans for a désirable spatial distribution of population were several times elabotared and revised. The share of the three Metropolitan areas dropped by 1965 below of 50 p. 100. 20 new towns were erected as régional centres. The policy of planned «dispersai» of population is continued, encounters however more and more difficulties on its pace.