Ammonia Beccarii Research Articles

Diet of the Chilean flamingo Phoenicopterus chilensis (Phoenicopteriformes: Phoenicopteridae) in a coastal wetland in Chiloé, southern Chile

BackgroundThe geographical distribution of the Chilean flamingo (Phoenicopterus chilensis) includes the southern-central Neotropics. Despite its wide distribution, currently there is no dietary information on its southern distribution range. From June to September 2011, we quantified the diet and prey availability of the Chilean flamingo in the marine wetland of Caulín (41°48' S, 73°37' W), southern Chile.ResultsThe prey availability related to both plankton and benthos were four species of copepods, four polychaetes, one foraminifera, and two amphipods. The diet of the Chilean flamingo was composed of foraminifera (Ammonia beccarii), copepods (Harpacticus sp.) and polychaetes. The most abundant prey items from feces of flamingos were Ammonia beccarii and Harpacticus sp. The diameter of A. beccarii consumed by flamingos ranged between 400 and 900 μm, while its width varied between 100 and 300 μm. The width of Harpacticus sp. consumed ranged between 160 and 260 μm. The similarity between flamingo diet and prey availability was 0.553. The diversity of prey organisms in the benthos was higher than that observed from plankton and feces of birds. A. beccarii was preferred over other prey consumed by flamingos. This preference is not related to the size of Harpacticus sp. but to their ability to swim and escape from flamingos.ConclusionsThe dietary similarity of the Chilean flamingo versus the availability of prey in the environment (plankton and benthos) was 55%, indicating that the Chilean flamingo is a partially selective predator.

Decalcification of benthic foraminifera due to “Hebei Spirit” oil spill, Korea

In order to determine the effects on foraminifera due to spilled crude oil in the “Herbei Spirit” incident, a study of benthic foraminiferal assemblages was carried out on sediment samples collected from the Sogeunri tidal flat, Taean Peninsula, Korea. Breakages of the chambers in the Ammonia beccarii and Elphidium subincertum species of the Sogeunri tidal flat with a low pH (6.98 on average) were marked. These chamber breakages occurred in 71.6% of A. beccarii and are thought to be caused by decalcification due to the fall in pH resulting from the “Hebei Spirit” oil spill. The factors that affect breakage of the chamber in benthic foraminifera under low pH condition may be not only deto decalcification but also to exposure duration of substrata in the tidal flat spilled crude oil.

Living and dead benthic foraminifera assemblages in the Bohai and northern Yellow Seas: Seasonal distributions and paleoenvironmental implications

Benthic foraminifera fossil shells are particularly useful in reconstructing water depth, temperature, the exported flux of organic carbon to the sea floor, and the level of bottom-water oxygenation in paleoenvironments. In this study, we investigated the living (stained) and dead (thanatocoenoses) benthic foraminifera assemblages collected in surface sediment samples from the Bohai Sea (BS) and the northern Yellow Sea (NYS). The samples were collected from different seasons, i.e. 50 samples in May (spring) and 46 samples in November (autumn). Our benthic foraminifera fauna analysis of these samples shows four living assemblages in May and three in November, indicating a sensitive response to seasonal environmental changes where the fauna live in the modern setting of the BS and NYS. Our redundancy analysis (RDA) of the living assemblages and their corresponding environmental parameters indicates that in spring, the abundances of Astrononion tasmanensis, Nonionella stella and Bulimina sp. have positive correlations with increased water depth, density and salinity, but are negatively correlated with increased FLOUR (chlorophyll). The abundances of Buccella frigid and Verneuilinulla advena are positively correlated with higher levels of dissolved oxygen (DO) and negatively correlated with increases in temperature. The abundances of Cribrononion subincertum are positively correlated with increased turbidity (TURB) and temperature, but negatively correlated with increased DO. In autumn, there is a positive correlation between the abundances of V. advena and increased salinity. Protelphidium tuberculatum, Ammonia beccarii (vars.) abundances, however, have negative correlations with salinity. During the autumn, the benthic foraminifera species P. tuberculatum was noticeably expanded and the dominance areas occupied by Elphidium magellanicum and C. subincertum were significantly reduced in the BS; along the southern coast of the Liaodong Peninsula, the dominant Buccella frigida in the spring was replaced by V. advena in autumn. The seasonal shifting of benthic foraminifera species are local responses to the combined changes in bottom water temperature, salinity, TURB and DO in the BS and NYS, and also to the more intensified autumn/winter intrusion of the Yellow Sea Warm Current (YSWC). The dead assemblages of benthic foraminifera, which are used to reconstruct paleoenvironments, exhibited considerable destruction of agglutinated assemblages. We found that such species as V. advena, Trochammina sp., Ammoscalaria sp. and Polskiammina asiatica are missing from the dead assemblages, possibly due to postmortem taphonomic processes in the BS and NYS. Considerable destruction of agglutinated species in dead assemblages may slightly bias our estimates of paleoenvironmental parameters when they are based on benthic foraminifera fossil shells.

Recent benthic foraminiferal assemblages and their relationship to environmental variables on the shoreface and inner shelf off Valencia (Western Mediterranean)

The environmental variables that determine the distributions of benthic foraminiferal assemblages on the shoreface and inner shelf of the north of Valencia province (Western Mediterranean) are identified. The possible influence of variables such as water depth, distance from shore, hydrodynamics, substrate type, carbonate content, organic matter content and human activity is evaluated. Multivariate cluster-Q-type analysis and redundancy analysis (RDA) are used to identify the environmental variables that have the greatest influence on the assemblage distribution.The spatial distribution of the assemblages is closely associated with water depth and substrate. The diversity and abundance of foraminifera shells increase with depth and their conservation improves. The most common species in the study area are Ammonia beccarii, Rosalina globularis, Buccella granulata, Planorbulina mediterranensis, and Lobatula lobatula. The presence of wastewater in the study area has not polluted the foraminiferal assemblages (absence of anomalous shells). The direction of the discharge plume is a potential source of nutrients for deep water.

Late Quaternary micropalaeontological record of a semi-enclosed marine basin, North Evoikos, central Aegean Sea

North Evoikos Gulf constitutes a deep (450 m) semi-enclosed basin in east-central Greece connected to the Aegean Sea via a 42-m sill to the north and a 40-m wide, 8-m deep channel to the south. Six gravity cores retrieved from different physiographic settings of the Gulf were analyzed for their benthic foraminiferal content, in order to reconstruct the local and regional palaeoenvironmental changes.Species Correspondence Analysis separates the foraminifera into 4 clusters: Cluster 1 is composed of Agglutinated species, Elphidium spp. and Ammonia beccarii; Cluster 2 is exclusively composed of Bulimina marginata; Cluster 3 consists of Bolivina spathulata and Bulimina costata and finally Cluster 4 comprises the 10 remaining species: Cibicides lobatulus, Cibicidoides pachyderma, Bulimina aculeata, Cancris oblonga, Melonis barleeanum, Chilostomella oolina, Cassidulina laevigata, Hyalinea balthica and Miliolidae. These clusters represent four distinct foraminiferal biofacies and are interpreted as reflecting different ecological conditions: Biofacies p-H corresponds to the proximal part of the shelf and it is characterised by the absence of foraminifera, skeletal debris and abundant peloids. Its topmost part shows an erosional surface, aged 32.4 ka, characterised by shell debris, and the appearance of few shallow marine benthic foraminifera. Biofacies Ia and Ib consist of a low-diversity Holocene assemblage which is mainly dominated by Textularia spp. and Elphidium spp., reflecting a low-energy restricted lagoon and the deeper water assemblage of B. marginata and H. balthica (Biofacies Ib) as well as by a mollusc assemblage dominated by Corbula gibba. These biofacies are only present in the mid-shelf setting. Biofacies II (Cluster 3: B. spathulata–B. costata) shows a possible positive correlation with nutrient contents and it exhibits a complementary pattern of distribution with Biofacies III (Cluster 4: B. marginata).Two main palaeoenvironmental settings were recognized: a) In the first setting dominated by Biofacies Ia and Ib, the succession of the benthic faunas is mainly controlled by the ongoing sea level rise; b) in the second setting, the species typical of shelf environment (C. laevigata–H. balthica) give way to opportunistic species (B. spathulata) and species that are more resistant to bottom water changes (B. marginata). This pattern is attributed to variations in the food chain and oxygenation.North Evoikos Gulf during the Uppermost Quaternary reflects a passive response to a globally fluctuating sea level that was not significantly modified by dramatic tectonic processes. Therefore, its palaeoceanographic evolution is primarily driven by climatic (eustatic) processes and accurately depicts local conditions.

DISTRIBUTION OF FORAMINIFERA IN A SUBTROPICAL BRAZILIAN ESTUARINE SYSTEM

The Santos Estuary, an estuarine system bordering the cities of Santos, Sao Vicente, and Cubatao in southeastern Brazil, contains the country’s largest harbor and main industrial center that have been impacted by industrial and domestic effluents since the late 19 th century. We report here on the distribution of benthic foraminifera and related environmental parameters in this estuary system during the summer and winter of 2007. The foraminiferal fauna is representative of mixohaline environments, and includes 107 live + dead taxa, of which 73 are calcareous benthic, 33 agglutinated, and one planktonic. Most of the calcareous specimens belong to the genera Ammonia, Elphidium , and Quinqueloculina and the species Nonionella atlantica . The living population was ~10% of the total foraminiferal fauna, and the dominant living species were similar to those in the total live + dead fauna. Ammonia beccarii was dominant in most of the stations during summer and winter. It could be considered opportunistic due to its high abundance in samples with low diversity and richness. It is not evident if the effects of human population density on the study area impacted the distribution of the foraminiferal fauna, because low proportions of deformed tests and low values of abundance, richness, and diversity were also found in pristine areas near Santos, Sao Vicente, and Cubatao.

Late pleistocene-holocene ostracod assemblages of the Northern Caspian Sea shelf

Analysis of the ostracod assemblages and the distribution of benthic foraminifera Ammonia beccarii in the core section GS 194-08-1 recovered at a depth of 7.5 m near the Volga delta front showed changes in environmental conditions in response to sea-level fluctuations. The pre-Novocaspian ostracod assemblage reflects the conditions that were dominant during the Late Khvalynian transgression, with a depth of about 20–30 m, and a salinity range of 12–13‰. The Early Novocaspian sediments contain an ostracod assemblage that represents a deeper water environment compared to the present, with an inferred depth of 12–16 m. The faunas from the younger Novocaspian sediments with abundant monospecific populations of Cyprideis torosa and co-occurring benthic foraminifera Ammonia beccarii represent modern-like environmental conditions.

Identification and Abundance of Benthic Foraminifera in Sediments of Southern Caspian Sea from Bahnamir to Babolsar, Iran

Shallow-water benthic foraminifera were identified from sediments of the southern part of the Caspian Sea (from Babolsar to Bahnamir). The samples were collected from 12 stations in the spring, of 2011. Sediment samples were gathered from depths up to 20 meters (5, 10, 15 and 20 m) by a Van Vein grab (0.1m 2 ); the environmental factors (dissolved oxygen, temperature, pH) were measured by an electrical multimeter. Total organic matter, calcium carbonate concentration, and grain size were calculated in the laboratory. A total of 5 species of benthic foraminifera obtained from the sediments were distinguished; four species identified respectively as Ammonia beccarii caspica Stschedrina , Elphidium littorale caspicus (Shokhina), Miliammina fusca (Brady), and Ammotium sp.; and one unidentified species. Ammonia beccarii caspica was dominant at all stations and Elphidium littorale caspicus was also observed at all stations. Structural abnormality in the tests of foraminifera (near all stations) pointed to a relatively polluted environment in the area studied.

Missing evidence for stepwise postglacial sea level rise and an approach to more precise determination of former sea levels on East China Sea Shelf

The vertical range of past sea level indicated by tidal flat deposits is equal to the sum of the sediment thickness and tidal range. Defining position of the dated sample in tidal flat deposits can increase the accuracy of former sea level determinations. The salt-water peaty layer often contains mixtures of autochthonous and allochthonous organic carbon and the tidal flat deposits may contain biological remains transported from shallow marine sources. These allochthonous remains have older ages than those of the layers containing the dated materials. Most published 14C data on the East China Sea Shelf are inadequate to define a precise postglacial sea level rise curve. Good results in determining both precise former sea levels and reliable 14C ages can be provided by selecting large plant roots and wood fragments from peaty layers, and selecting less worn foraminifera tests and mollusk shells of dominant species in modern equivalent environments (such as foraminifera Ammonia beccarii vars. or mollusk Corbicula fluminea) from the peaty layer, its close overlying deposits and the base of tidal flat deposits without a basal peaty layer. The stepwise model for postglacial sea level rise on the East China Sea Shelf (Liu, 2001; Liu et al., 2004) was mostly determined by freshwater peat, shallow marine and subtidal samples, which cannot provide precise water levels. The reliability of many 14C ages used is also questionable due to unknown proportions of allochthonous material. Thus the stepwise model is unsupported by available data. A rough sea level curve in last 13,000 yr on the East China Sea Shelf is herein proposed. It seems simple but is effective based on valid data.

Phase evolution of Holocene paleoenvironmental changes in the southern Yellow Sea: Benthic foraminiferal evidence from core C02

Assemblages of benthic foraminifera in a sediment core (C02) near the western margin of the southern Yellow Sea Mud were studied to decipher the phase evolution of Holocene paleoenvironmental changes associated with the Holocene marine transgression. It appears that during the early Holocene (11.2-10.1 kyr BP), the faunal was dominated by low salinity and shallow water species Cribrononion subincertum, Buccella frigida and Ammonia beccarii, reflecting a near coast depositional environment. A rapid increase of the relative abundance of Ammonia compressiuscula between 10.1-9.3 kyr BP indicates that the sea level rose rapidly during that time period. From 9.3-7.7 kyr BP, the benthic foraminiferal assemblage was dominated by high percentage of A. compressiscula, suggesting that the sea level was relatively stable. An obvious transition of benthic foraminifera, from the A. compressiuscula-dominated assemblage to an Ammonia ketienziensis-dominated assemblage, occurred between 7.7-6.2 kyr BP, possibly corresponding to a second sea level rapid rise period in the Yellow Sea during the Holocene. This transition may correspond to the gradually strengthened Yellow Sea warm current (YSWC) and finally is established the modern-type circulation in the Yellow Sea. It may also mark the formation of the Yellow Sea cold bottom water (YSCBW) during that period. Since then, the benthic foraminiferal assemblage based on core C02 was dominated by typical YSCBW species, A. ketienziensis, Astrononion italicum and Hanzawaia nipponica, at 6.2-4 kyr BP. A non-deposition period occurred since similar to 4 kyr BP, which possibly related to the hydrology changes caused by the East Asia monsoon. The two obvious benthic foraminiferal transitions recorded in core C02 during the early and middle Holocene provide evidence that the Yellow Sea has undergone a two-phase rapid sea level rise during the Holocene marine transgression.

SPATIAL DISTRIBUTION AND ASSEMBLAGE STRUCTURE OF FORAMINIFERA IN NAYBAND BAY AND HALEH ESTUARY, NORTH-WEST OF THE PERSIAN GULF

The spatial distribution of benthic foraminiferal assemblage of Nayband Bay and Haleh Estuary in the North-West of the Persian Gulf, was explored during 2011-2012 . The relationship between spatial pattern of foraminifera assemblages and the ambient factors (i.e. water temperature, salinity, pH, dissolved oxygen, sediment grain size distribution, sediment organic content, and CaCO3 concentration of sediments) was measured. The most abundant benthic foraminifera species which were found in the studied area include Ammonia beccarii, Eponides repandus, Quinqueloculina sp., Elphidium sp. The two most abundant species belongs to Rotaliidae family. The specimen groups presented in the study area were somehow the same, and their relative abundance did not vary tremendously in sites consisting of foraminifera assemblages. The fauna shows affinities to those of the southern coastline of the Persian Gulf and also the Oman Sea. The BIO-ENV analysis identified temperature, salinity, pH, and total organic matter as the major environmental variables influencing the infaunal pattern. Generally foraminiferal populations were sparse in the study area, which may be due to the low depth and consequently, low distribution of foraminiferal specimens.

ECOLOGICAL ASSESSMENT IN SEMARANG COASTAL WATER

Coastal water is vulnerable to anthropogenic substances such as human activities by product in coastal land and upper land area. Semarang coastal area is one of areas which has progressive development in northern coastal of Java Island. The aim of this study was to evaluate ocean health status based on heavy metal contain and benthic foraminiferal characteristics as the bioindicator. Sampling and laboratory activities were carried out in August 2010. Sampling stations were located on the estuaries of Western Canal Flood, Tanjung Mas Port and Eastern Canal Flood. The result showed that Tanjung Mas pool port had the highest Pb, Zn,and Total Organic Compounds (TOC) concentrations. The average of abnormal test of benthic foraminiferal (Ammonia beccarii) were also higher in Tanjung Mas port than in eastern and western canal flood. Keywords: assessment, coastal water, Semarang.

Influence of the environmental characteristics of mangrove forests on recent benthic foraminifera in the Gulf of Urabá, Colombian Caribbean

Mangrove forests with different characteristics have developed in the Gulf of Urabá (Colombia). Eighty-two sediment samples were studied for species of foraminifera and their environmental dependence. Ten agglutinated species and one calcareous species dominated in these mangroves. Foraminifera were absent in mangrove areas exposed to high hydraulic energy (waves) or high human affectation. Two characteristic assemblages were found. The first one, represented by Milliammina fusca, the most dominant species, was related to finer substrates and lower salinities. The second one, represented by Ammonia beccarii, the most common calcareous species, was found in polluted low-oxygen environments. Haplophragmoides canariensis and Trochammina squamata, small species, showed a preference for places with abundant organic matter. A conceptual model is proposed that relates the benthic foraminifera to the hydrodynamics, grain size, organic matter content, and pollution.

Benthic foraminifera as proxies of pollution: The case of Guanabara Bay (Brazil)

Due to economic importance of Guanabara Bay, a multidisciplinary approach was adopted to investigate 88 surficial sediment samples in order to use the benthic foraminifera as indicators for the characterization of environmental variations. Grain-size analyses indicate that bottom sediments of the inner part of the bay are mainly muddy while those close to the entrance of the bay are sandy. Geochemical data show high concentration of heavy metals mainly in the northern region of the bay. Micropalaeontological analyses indicate the boundaries of the areas with the highest concentration of heavy metals. The dominant benthic foraminifera in the bay are Ammonia beccarii and Buliminella elegantissima, taxa capable of differentiating the presence of pollutants of different sources. B. elegantissima, in particular, has shown to be an indicator of anthropogenic pollution. The study highlights the worsening of environmental conditions since 2000 and those areas of the bay in need of a priority recovery.

Recent oxygen depletion in the Pearl River Estuary, South China: geochemical and microfaunal evidence

We examined a suite of geochemical and microfaunal indicators in 210Pb-dated sediment cores from the Pearl River Estuary, South China, to determine the historical course of oxygen conditions. The results revealed a substantial increase in nutrient elements and primary production in the sediment over the last 3 decades, which could be interpreted as a recent increase in the extent of eutrophic condition in the Pearl River Estuary. Furthermore, total foraminifers decreased abruptly in abundance while the species Ammonia beccarii, which is tolerant of low-oxygen conditions and high organic fluxes, showed a marked increase in relative abundance after the 1970s. These faunal changes implied that significant deterioration had occurred in the bottom water oxygen conditions since the late 1970s. This degradation could be caused by the increased nutrient and organic loading to the estuarine system, which is likely related to the rapid urbanization and industrial development in the Pearl River Delta during this period.

Utility of sub-surface benthic foraminiferal assemblages to decipher the paleoenvironment of the north-west Kerala coast

Benthic foraminifera have proved to be reliable proxies for understanding paleoenvironmental changes or paleoclimatic changes in the past geological history of the Earth, especially since the Cambrian when these unicellular protozoans began to evolve. Since then, foraminifers have been recorded as fossils and their abundant occurrence in the fossil record has aided in understanding the past history of the Earth. Within the Holocene, this group of microfossils has proved to be of immense utility, as their assemblages could be utilized for understanding past environmental changes, as they are so sensitive to variations in such ecological parameters as pH, depth of the water column, salinity, dissolved oxygen content, nature of substrate calcium carbonate and organic contents, which are the primary controlling factors over their species populations and diversity. The study area is a part of Kannur District, Kerala, India, about 5–7 km from the present-day shoreline. Trench samples (sub-surface) at varying depths up to 3.6 m, at Karakkeezhu and Kuduvathala, yielded a benthic foraminiferal assemblage that is characteristic of modern estuarinelbrackish water environments. This assemblage, typified by the dominance of Ammonia beccarii (Linnaeus) and its associated species, is suggestive of a shallow, probably sheltered, tidal flat environment with a possible connection to the Arabian Sea ∼5,000 to 5,500 years B.P. as revealed by 14C dates of both mollusk shells and sediment samples. The study has thrown open some intriguing questions, particularly with regard to the complete absence of arenaceous, agglutinated forms (Suborder TEXTULARIINA) and the poor representation of calcareous, imperforate taxa (Suborder MILIOLINA).

DISTRIBUTION OF LIVING BENTHIC FORAMINIFERA ON THE NORTHERN GULF OF CADIZ CONTINENTAL SHELF

Living (stained) benthic foraminiferal faunas were analyzed in 51 surficial sediment samples taken from the northern Gulf of Cadiz continental shelf between the mouths of the Guadiana and Guadalquivir rivers. The distribution and abundance of 26 species with relative abundance >5% were related to water depth, sediment type, river discharge, water temperature, salinity, turbidity, and primary productivity. Hierarchical classification using R- and Q-mode cluster analyses, and individual distributions, allowed these taxa to be categorized into four general groups. Group 1 is represented by Bolivina ordinaria and Hopkinsina atlantica. These species are linked to river discharge, and are associated with muddy sediments. They are considered the most opportunistic species in the assemblage, and are associated with the limits of productivity. Group 2, contains Ammonia beccarii, Eggerelloides scaber, Elphidium gerthi, Quinqueloculina laevigata, and Q. stelligera, and is characteristic of shallow water depths. Its species are associated with different sediment types and their distribution is influenced by river discharge. Group 3 is dominated by Bulimina aculeata, B. elongata, Elphidium excavatum, E. cuvillieri, Epistominella vitrea, and Rectuvigerina phlegeri. These species display the highest abundances between 30–100 m water depths. They prevail in muds associated with weak hydrodynamics, low oxygenation, and high organic matter. Group 4 includes species that are more abundant in deep stations and is divided into two subgroups. Subgroup 4A includes Bolivina catanensis, B. italica, B. striatula, Cassidulina laevigata, Stainforthia sp., Nouria polymorphinoides, and Nouria sp., with higher abundances in one or two samples. Subgroup 4B, with Brizalina dilatata, B. spathulata, Bulimina marginata, Nonionella iridea, N. stella, and N. turgida, has patchy distribution. Higher abundances of Nonionella species off the Guadiana River are related to low temperature and salinity.

THE CHARACTERISTICS OF FORAMINIFERAL COMMUNITY IN JAKARTA BAY

<p>Jakarta bay is a unique water since there are hydrological and ecological complexity. In general, the feature of these water consist of three ecological elements that are estuaries, coral reefs and open sea. Each of these ecological element has different hydrology, ecology as well as biological characteristics. As a form of meiobenthic community, foraminifera has adaptive behavior to each of ecological element of the waters. The observation on foraminiferal adaptive behavior due to the hydrological condition of Jakarta Bay was conducted from 2003 to 2009. The result showed that foraminiferal distribution was tend to pursue to the degradation water conditions and constructed a specific pattern. Coastal water and estuary were found dominated by Ammonia beccarii, Calcarine and other larger benthic foraminifera were common in coral reef area, Elphidium and Nonion depressulum were common in open waters area. Based on the diversity indices, the foraminifera in Jakarta Bay has a higher diversity compared to foraminifera in the coastal water of Semarang and Cirebon and among the ecological element of Jakarta Bay, reef area has the highest diversity index than coastal nor open sea area.</p><p>Keywords: Foraminifera, Calcarine, Jakarta Bay</p>

THE CHARACTERISTICS OF FORAMINIFERAL COMMUNITY IN JAKARTA BAY

Jakarta bay is a unique water since there are hydrological and ecological complexity. In general, the feature of these water consist of three ecological elements that are estuaries, coral reefs and open sea. Each of these ecological element has different hydrology, ecology as well as biological characteristics. As a form of meiobenthic community, foraminifera has adaptive behavior to each of ecological element of the waters. The observation on foraminiferal adaptive behavior due to the hydrological condition of Jakarta Bay was conducted from 2003 to 2009. The result showed that foraminiferal distribution was tend to pursue to the degradation water conditions and constructed a specific pattern. Coastal water and estuary were found dominated by Ammonia beccarii, Calcarine and other larger benthic foraminifera were common in coral reef area, Elphidium and Nonion depressulum were common in open waters area. Based on the diversity indices, the foraminifera in Jakarta Bay has a higher diversity compared to foraminifera in the coastal water of Semarang and Cirebon and among the ecological element of Jakarta Bay, reef area has the highest diversity index than coastal nor open sea area.Keywords: Foraminifera, Calcarine, Jakarta Bay

ANTHROPOGENIC IMPACT ON BENTHIC FORAMINIFERA, ABU-QIR BAY, ALEXANDRIA, EGYPT

The present study examines the foraminiferal distribution in recent bottom sediments of Abu-Qir Bay located along the Mediterranean coast of Alexandria, Egypt. Abu-Qir Bay receives substantial amounts of heavy metals from the surrounding industrial area, as well as agricultural and domestic effluents, which makes it one of the most polluted areas along the Mediterranean coast. Information provided by the benthic foraminiferal associations was integrated with geochemical, sedimentological, and water data to characterize the environments. The benthic foraminifera are recognized as potential indicators of pollution in coastal marine environments. Surface sediment samples were collected in two seasons (May and November) from nine sites. Cluster analysis and Canonical Correspondances Analysis reveal a distinct boundary that separates two areas; the more-polluted stations nearshore, and the less-polluted stations offshore The first area is characterized by sediment with high silt and clay content and rich in total organic carbon, and bottom water with relatively high temperatures, but low in dissolved oxygen, salinity, transparency, and pH. Its foraminiferal fauna is dominated by Ammonia tepida, Quinqueloculina lata , and Porosononion spp., which are species considered as pollution opportunists. The second area is characterized by coarser sediment overlain by bottom waters high in dissolved oxygen, and transparent, saline, cold water, and is dominated mainly by Quinqueloculina vulgaris, Elphidium spp., Asterigerinata mamilla, Rosalina macropora, Ammonia beccarii, Triloculina trigonula, Peneroplis pertusus , and Quinqueloculina spp. Heavy-metal pollutants have a deleterious effect on benthic foraminifera that results in reduced population diversity, increased dominance, and deformed tests.