scholarly journals Linking Microbial Functioning and Trophic Pathways to Ecological Status in a Coastal Mediterranean Ecosystem

Water ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1325
Author(s):  
Franco Decembrini ◽  
Carmela Caroppo ◽  
Gabriella Caruso ◽  
Alessandro Bergamasco
Keyword(s):  
Coastal Waters ◽  
Sea Water ◽  
Ecological Status ◽  
Mediterranean Ecosystem ◽  
The North ◽  
Coastal Marine ◽  
Prokaryotic Abundance ◽  
Trophic Pathways ◽  
Terrestrial Inputs ◽  
Heterotrophic Production

Coastal marine ecosystems host complex microbial communities whose composition and metabolism are influenced by continental inputs and mesoscale properties of seawater masses. The identifying traits of the phytoplankton and bacteria such as biomass, size, shape and their metabolism related to organic matter production and degradation, recognized as indicators of the functioning of an ecosystem, were observed in the Gulf of Manfredonia (South Adriatic Sea, Italy) in late spring. This Gulf area is characterized by terrestrial inputs and mesoscale circulation influence such as coastal waters flowing southward from the North Adriatic and offshore waters interested by the Ionian Sea. Water samples were grouped in clusters (Coastal, Intermediate, Offshore and Deep Systems) according to the water column properties. Phytoplankton community biomass and composition, autotrophic and total prokaryotic abundances and microbial metabolism such as enzyme activity rates and prokaryotic heterotrophic production were analyzed to elucidate the trophic pathways with the objective to infer on the ecosystem status. As expected, size-fractionated phytoplankton biomass and production showed greater concentration in coastal waters with prevalence of the largest fractions (micro- and nano-) supported by the diatoms. Conversely, lower biomass and production were measured in all off-shore waters, mainly sustained by smallest fractions (nano-sized phytoflagellates and picophytoplankton). Total and autotrophic prokaryotic abundance decreased from coastal to offshore stations, inversely with respect to cell volume. Prokaryotic heterotrophic production was just below 50% compared to that of phytoplankton in all waters, evidencing an active biomass synthesis. High alkaline phosphatase and leucine aminopeptidase in coastal and offshore waters suggested the quick regeneration of Phosphorus and protein decomposition, respectively. Different levels of phytoplankton-bacteria association might provide a tool to define the ecological status of the studied system in the observed period; an approach to ecosystem assessment exportable to other coastal systems is proposed.

scholarly journals Distribusi mikroplastik di perairan Pulau Bengkalis Kabupaten Bengkalis Provinsi Riau

DEPIK ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 386-392
Author(s):  
Intan Suci Febriani ◽  
Bintal Amin ◽  
M. Fauzi
Keyword(s):  
Coastal Waters ◽  
Sea Water ◽  
Anthropogenic Activities ◽  
Mesh Size ◽  
Demersal Fish ◽  
Sampling Location ◽  
The North ◽  
Average Abundance ◽  
Seawater Samples ◽  
North And South

Microplastics are particles that have a size of 5 mm, where its existence might be able to contaminate the biota in the aquatic environment. This research was conducted in the coastal waters of Bengkalis Island in December 2020 with the aim to determine the types and analyze its abundance of microplastics in each area with different sources of anthropogenic input in the north and south Bengkalis Island. Sampling of sea water for microplastic analysis was done using plankton net (diameter 30 cm and mesh size 30 μm) from six sampling stations. Thirty six individual samples of Duri (Arius maculatus), Lomek (Harpodon nehereus), and Biang (Setipinna breviceps) fish were obtained with the help of local fishermen in each sampling location. The results showed that the types of microplastics found in seawater samples are fiber and film with average abundance ranges between 9.58 particles/m3 - 40.42 particles/m3. The highest abundance was found in station 6 (60.83 ± 8.61 particles/m3 and 20.00 ± 8.94 particles/m3) for fiber and film, whilst the lowest abundance was found in station 3 (12.50 ± 5.24 particles/m3 and 6.67 ± 6.06 particles/m3) for fiber and film, respectively. The average abundance of microplastics found in the digestive tract of fish was 62.96 particles/ind. which consisted of fiber, film and fragment. The highest microplastic abundance was found in Duri fish (72.22 particles/ind.), whilst the lowest was found in Lomek fish (55.56 particles/ind.). Although the abundance of microplastic in coastal waters of north Bengkalis were higher than that in the south of Bengkalis Island, statistically they were significantly different. This was presumably due to differences in oceanographic influences such as current and waves between the two water masses as well as anthropogenic activities in both areas that can affect the spread and distribution of microplastics.Keywords: plastic waste, Bengkalis waters, demersal fish, pelagic fishABSTRAKMikroplastik adalah partikel yang memiliki ukuran 5 mm, di mana keberadaannya dapat mencemari biota di lingkungan akuatik. Penelitian ini dilakukan di perairan pantai Pulau Bengkalis pada Desember 2020 dengan tujuan untuk menentukan jenis dan menganalisis kelimpahan mikroplastik di setiap wilayah dengan berbagai sumber input antropogenik bagian utara dan selatan Pulau Bengkalis. Pengambilan sampel air laut untuk analisis mikroplastik dilakukan menggunakan plankton net (diameter 30 cm dan ukuran jala 30 μm) dari enam stasiun pengambilan sampel. Tiga puluh enam sampel individu ikan Duri (Arius maculatus), Lomek (Harpodon nehereus), dan Biang (Setipinna breviceps) diperoleh dengan bantuan nelayan lokal di setiap lokasi pengambilan sampel. Hasil penelitian menunjukkan bahwa jenis mikroplastik yang ditemukan dalam sampel air laut adalah fiber dan film dengan kisaran kelimpahan rata-rata antara 9,58 partikel/m3 - 40,42 partikel / m3. Kelimpahan tertinggi ditemukan di stasiun 6 (60,83 ± 8,61 partikel / m3 dan 20,00 ± 8,94 partikel / m3) untuk fiber dan film, sedangkan kelimpahan terendah ditemukan di stasiun 3 (12,50 ± 5,24 partikel / m3 dan 6,67 ± 6,06 partikel / m3) untuk fiber dan film. Kelimpahan rata-rata mikroplastik yang ditemukan dalam saluran pencernaan ikan adalah 62,96 partikel / ind. yang terdiri dari fiber, film dan fragmen. Kelimpahan mikroplastik tertinggi ditemukan pada ikan Duri (72,22 partikel / ind.), sedangkan yang terendah ditemukan pada ikan Lomek (55,56 partikel / ind.). Meskipun kelimpahan mikroplastik di perairan pantai Bengkalis utara lebih tinggi daripada di selatan Pulau Bengkalis, secara statistik mereka berbeda nyata. Ini mungkin karena perbedaan dalam pengaruh oseanografi seperti arus dan gelombang antara dua massa air serta aktivitas antropogenik di kedua daerah yang dapat mempengaruhi penyebaran dan distribusi plastik mikro.Kata kunci: sampah plastik, perairan Bengkalis, ikan demersal, ikan pelagis

COMPARATIVE CHARACTERISTIC OF SEA RADIANCE COEFFICIENT SPECTRA MEASURED REMOTELY IN COASTAL WATERS OF FIVE SEAS

2017 ◽  
Author(s):  
Vera Rostovtseva ◽  
Vera Rostovtseva ◽  
Igor Goncharenko ◽  
Igor Goncharenko ◽  
Dmitrii Khlebnikov ◽  
...  
Keyword(s):  
Sea Water ◽  
Calibration Method ◽  
Aral Sea ◽  
Comparative Characteristic ◽  
The Black Sea ◽  
North East ◽  
The North ◽  
Water Constituents ◽  
Characteristic Features ◽  
The Baltic

Sea radiance coefficient, defined as the ratio of the sunlight reflected by the water bulk to the sunlight illuminating the water surface, is one of the most informative optical characteristics of the seawater that can be obtained by passive remote sensing. We got the sea radiance coefficient spectra by processing the data obtained in measurements from board a moving ship. Using sea radiance coefficient optical spectra it is possible to estimate water constituents concentration and their distribution over the aquatory of interest. However, thus obtained sea radiance coefficient spectra are strongly affected by weather and measurement conditions and needs some calibration. It was shown that practically all the spectra of sea radiance coefficient have some generic peculiarities regardless of the type of sea waters. These peculiarities can be explained by the spectrum of pure sea water absorption. Taking this into account a new calibration method was developed. The measurements were carried out with the portative spectroradiometers from board a ship in the five different seas: at the north-east coast of the Black Sea, in the Gdansk Bay of the Baltic Sea, in the west part of the Aral Sea, in the Kara Sea with the Ob’ Bay and in the Philippine Sea at the coast of Taiwan. The new method of calibration was applied to the obtained spectra of the sea radiance coefficient that enabled us to get the corresponding absorption spectra and estimate the water constituents concentration in every region. The obtained concentration estimates were compared to the values obtained in water samples taken during the same measurement cycle and available data from other investigations. The revealed peculiarities of the sea radiance coefficient spectra in the aquatories under exploration were compared to the corresponding water content and some characteristic features were discussed.

scholarly journals Transboundary geophysical mapping of geological elements and salinity distribution critical for the assessment of future sea water intrusion in response to sea level rise

2012 ◽  
Vol 16 (7) ◽  
pp. 1845-1862 ◽  
Author(s):  
F. Jørgensen ◽  
W. Scheer ◽  
S. Thomsen ◽  
T. O. Sonnenborg ◽  
K. Hinsby ◽  
...  
Keyword(s):  
Groundwater Flow ◽  
Sea Level Rise ◽  
Sea Level ◽  
Preferential Flow ◽  
Sea Water ◽  
Saline Water ◽  
Seismic Survey ◽  
Salinity Distribution ◽  
Geological Structures ◽  
The North

Abstract. Geophysical techniques are increasingly being used as tools for characterising the subsurface, and they are generally required to develop subsurface models that properly delineate the distribution of aquifers and aquitards, salt/freshwater interfaces, and geological structures that affect groundwater flow. In a study area covering 730 km2 across the border between Germany and Denmark, a combination of an airborne electromagnetic survey (performed with the SkyTEM system), a high-resolution seismic survey and borehole logging has been used in an integrated mapping of important geological, physical and chemical features of the subsurface. The spacing between flight lines is 200–250 m which gives a total of about 3200 line km. About 38 km of seismic lines have been collected. Faults bordering a graben structure, buried tunnel valleys, glaciotectonic thrust complexes, marine clay units, and sand aquifers are all examples of geological structures mapped by the geophysical data that control groundwater flow and to some extent hydrochemistry. Additionally, the data provide an excellent picture of the salinity distribution in the area and thus provide important information on the salt/freshwater boundary and the chemical status of groundwater. Although the westernmost part of the study area along the North Sea coast is saturated with saline water and the TEM data therefore are strongly influenced by the increased electrical conductivity there, buried valleys and other geological elements are still revealed. The mapped salinity distribution indicates preferential flow paths through and along specific geological structures within the area. The effects of a future sea level rise on the groundwater system and groundwater chemistry are discussed with special emphasis on the importance of knowing the existence, distribution and geometry of the mapped geological elements, and their control on the groundwater salinity distribution is assessed.

scholarly journals Land-use and agriculture in Denmark around year 1900 and the quest for EU Water Framework Directive reference conditions in coastal waters

AMBIO ◽  
2021 ◽  
Author(s):  
Bent T. Christensen ◽  
Birger F. Pedersen ◽  
Jørgen E. Olesen ◽  
Jørgen Eriksen
Keyword(s):  
Land Use ◽  
Water Framework Directive ◽  
Coastal Waters ◽  
Root Zone ◽  
Reference Conditions ◽  
Ecological Status ◽  
Agricultural Activity ◽  
Eu Water Framework Directive ◽  
Alternative Approach ◽  
The Eu

AbstractThe EU Water Framework Directive (WFD) aims to protect the ecological status of coastal waters. To establish acceptable boundaries between good and moderate ecological status, the WFD calls for reference conditions practically undisturbed by human impact. For Denmark, the nitrogen (N) concentrations present around year 1900 have been suggested to represent reference conditions. As the N load of coastal waters relates closely to runoff from land, any reduction in load links to agricultural activity. We challenge the current use of historical N balances to establish WFD reference conditions and initiate an alternative approach based on parish-level land-use statistics collected 1896/1900 and N concentrations in root zone percolates from experiments with year 1900-relevant management. This approach may be more widely applicable for landscapes with detailed historic information on agricultural activity. Using this approach, we find an average N concentration in root zone percolates that is close to that of current agriculture. Thus, considering Danish coastal waters to be practically unaffected by human activity around year 1900 remains futile as 75% of the land area was subject to agricultural activity with a substantial potential for N loss to the environment. It appears unlikely that the ecological state of coastal waters around year 1900 may serve as WFD reference condition.

scholarly journals Carbon-14 in the Southern Indian Ocean

Radiocarbon ◽  
1980 ◽  
Vol 22 (3) ◽  
pp. 684-692 ◽  
Author(s):  
Georgette Delibrias
Keyword(s):  
Surface Water ◽  
Indian Ocean ◽  
Water Samples ◽  
Sea Water ◽  
Time Lag ◽  
Vertical Profiles ◽  
Carbon 14 ◽  
Middle Latitudes ◽  
The North ◽  
The Indian Ocean

14C measurements were carried out on sea water samples collected in 1973, in the Indian ocean. The results obtained for 9 vertical profiles between 27° S and 48°S are presented. In surface water, the bomb 14C content is maximum at middle latitudes. A time lag relative to the north hemisphere bomb 14C delivery is apparent. In the more southern latitudes, 14C content remains very low.

Temperature, Salinity and Plankton in the Eastern North Atlantic and Coastal Waters of Britain, 1957.: I. The Characterisation and Distribution of Surface Waters

1963 ◽  
Vol 20 (3) ◽  
pp. 789-826 ◽  
Author(s):  
B. McK. Bary
Keyword(s):  
North Sea ◽  
North Atlantic ◽  
Coastal Waters ◽  
Water Bodies ◽  
English Channel ◽  
Oceanic Water ◽  
Climatic Fluctuations ◽  
The North ◽  
The North Sea ◽  
Eastern North Atlantic

Monthly temperature-salinity diagrams for 1957 have demonstrated that three surface oceanic "water bodies" were consistently present in the eastern North Atlantic; two are regarded as modified North Atlantic Central water which give rise to the third by mixing. As well in the oceanic areas, large and small, high or low salinity patches of water were common. Effects of seasonal climatic fluctuations differed in the several oceanic water bodies. In coastal waters, differences in properties and in seasonal and annual cycles of the properties distinguish the waters from the North Sea, English Channel and the western entrance to the Channel.The geographic distributions of the oceanic waters are consistent with "northern" and "southern" water bodies mixing to form a "transitional" water. Within this distribution there are short-term changes in boundaries and long-term (seasonal) changes in size of the water bodies.Water in the western approaches to the English Channel appeared to be influenced chiefly by the mixed, oceanic transitional water; oceanic influences in the North Sea appear to have been from northern and transitional waters.

Modeling Transit Flow Through Port Gates and Connecting Channel in Baltic Sea—Liepaja Port—Liepaja Lake System

2021 ◽  
Vol 8 ◽  
Author(s):  
Vilnis Frishfelds ◽  
Juris Sennikovs ◽  
Uldis Bethers ◽  
Jens Murawski ◽  
Andrejs Timuhins
Keyword(s):  
Baltic Sea ◽  
Sea Level ◽  
Sea Water ◽  
Lake System ◽  
The North ◽  
Transit Flow ◽  
Trade Channel ◽  
Calm Weather ◽  
Set Up ◽  
The Baltic

This study investigates a water transport features by extending Copernicus Marine Environment Service (CMEMS) to the Liepaja coast-port-channel-lake system with a two-way nested model. The Liepaja lake and Liepaja port are connected by Trade channel. The Liepaja port has three gates—the openings in wave breakers connecting the port aquatory with the Baltic sea. Each of gates has a corresponding dredged channel for securing the navigation. A hydrodynamic model is set up to study the flow and water level in this system. The area of the port gates, port and Trade channel are resolved by 33 m grid. The model results are verified against currents and sea level observations inside/outside port, Trade channel and Liepaja lake. Results and observations show that strong currents occur in the Trade channel in case of rapid sea level change in Baltic sea despite the Trade channel is rather shallow at the connection with Liepaja lake. The northern part of the Liepaja lake gets filled with brackish water during storm surge events. The channel has notable alternating current also during a relatively calm weather due to the port seiches. Long and narrow shape of the channel implies the Helmholtz type oscillations between the lake and the port with a period in approximately semidiurnal range. Hydrodynamic simulations describe well these oscillations but the phase of hourly scale oscillations in the port may differ in case of weak external forcing. Water exchange is significantly increased by the transit (gate to gate) sea currents. This transit flow usually occurs between South or Central gate and the North gate carrying sea water into the port. Northward flow of the surface layer is more characteristic in the port aquatory due the prevailing south-western winds. There are intense morphological processes at the coastline and underwater slope near the Liepaja port due to a sandy western coastline of Latvia, long fetch of the waves and strong currents at the port gates. Liepaja port is one of the Latvian ports in HywasPort operational service of hydrodynamics, waves and siltation.

scholarly journals Spatiotemporal variation in size-structured populations using fishery data: an application to shortfin mako (Isurus oxyrinchus) in the Pacific Ocean

2017 ◽  
Vol 74 (11) ◽  
pp. 1765-1780 ◽  
Author(s):  
Mikihiko Kai ◽  
James T. Thorson ◽  
Kevin R. Piner ◽  
Mark N. Maunder
Keyword(s):  
Coastal Waters ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Marine Species ◽  
Structured Populations ◽  
Spatiotemporal Model ◽  
The North ◽  
Isurus Oxyrinchus ◽  
Shortfin Mako ◽  
Catch Rates

We develop a length-disaggregated, spatiotemporal, delta-generalized linear mixed model (GLMM) and apply the method to fishery-dependent catch rates of shortfin mako sharks (Isurus oxyrinchus) in the North Pacific. The spatiotemporal model may provide an improvement over conventional time-series and spatially stratified models by yielding more precise and biologically interpretable estimates of abundance. Including length data may provide additional information to better understand life history and habitat partitioning for marine species. Nominal catch rates were standardized using a GLMM framework with spatiotemporal and length composition data. The best-fitting model showed that most hotspots for “immature” shortfin mako occurred in the coastal waters of Japan, while hotspots for “subadult and adult” occurred in the offshore or coastal waters of Japan. We also found that size-specific catch rates provide an indication that there has been a recent increasing trend in stock abundance since 2008.

scholarly journals The holoplankton of the Santa Catarina coast, southern Brazil

2011 ◽  
Vol 83 (2) ◽  
pp. 575-588 ◽  
Author(s):  
Charrid Resgalla Jr
Keyword(s):  
Coastal Waters ◽  
Zooplankton Community ◽  
The State ◽  
Zooplankton Abundance ◽  
Santa Catarina ◽  
The North ◽  
Or Groups ◽  
Parvocalanus Crassirostris ◽  
Water Species ◽  
Potential Use

This paper presents information from different sampling surveys carried out along the Santa Catarina coast in order to outline the biogeographical characteristics of the zooplankton in this region and identify species or groups of species with potential use as bioindicators. Based on a checklist of species of the zooplankton community in the state, it was observed that, in the warmer months of the year, the fauna is similar to that of the states of Paraná and São Paulo (e.g. Creseis virgula f. virgula, Penilia avirostris; Acartia lilljeborgi and Oithona oswaldocruzi), while in the colder months there are coastal representatives of the fauna of Rio Grande do Sul (e.g. Acartia tonsa). However, the zooplankton consists predominantly of warm water species for most of the year, which is typical of Tropical Shelf Waters. Various species of zooplankton can be used as hydrological indicators, enabling a distinction to be made between coastal waters which are influenced by continental inputs (e.g. Paracalanus quasimodo and Parvocalanus crassirostris), common in the north of the state, and processes of upwelling (e.g. Podon intermedius) and the influence of the Subtropical Shelf Front (e.g. Pleopis polyphemoides), coming from the south. The different environments investigated present a zooplankton abundance that depends on the influence of continental inputs and the possibility of their retaining and contribution for the coastal enrichment, which varies seasonally

Motility and energy-rich phosphorus compounds in spermatozoa of Octopus dofleini martini

1971 ◽  
Vol 178 (1051) ◽  
pp. 151-160 ◽  
Keyword(s):  
Sea Water ◽  
Phosphorus Compounds ◽  
Short Exposure ◽  
Motile Sperm ◽  
High Concentration ◽  
Irreversible Loss ◽  
Prolonged Incubation ◽  
The North ◽  
Sperm Suspension ◽  
The North Pacific

The spermatozoa of the giant octopus of the North Pacific, freshly removed from spermatophores, showed very little motility, but on dilution with sea-water or 2.7 % NaCl, followed by dialysis against either of these two media, they became intensely motile and remained so for several days at 2 to 10 °C. At higher temperatures, particularly above 25 °C, octopus spermatozoa lost their motility rapidly. At 35 °C, complete and irreversible loss of motility occurred within less than 1 min. The motility of octopus spermatozoa at 2 to 10 °C persisted under both anaerobic and aerobic conditions and did not require the presence of exogenous glycolysable sugar. The addition of spermatophoric plasma to a motile sperm suspension inhibited motility. Other inhibitors were sodium azide, 2, 4-dinitrophenol and ethylenediaminetetra-acetate, at 0.001 M concentrations. ATP, ADP and arginine phosphate have been identified and quantitatively measured in octopus spermatozoa. On prolonged incubation of motile sperm suspensions a t 3 °C, ATP and ADP did not decline appreciably, whilst arginine phosphate decreased considerably. The decrease was even more pronounced in sperm suspensions which had first been inactivated by short exposure to 35 °C, prior to prolonged incubation at 3 °C. Glycogen, the main carbohydrate store of octopus spermatozoa, remained at a high concentration even in sperm suspensions kept for 5 days at 3 °C, and there was no appreciable difference in that respect between a sample containing motile spermatozoa and one in which, at the outset of incubation, the spermatozoa were immobilized by heating to 35 °C.

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