scholarly journals Particle sources and transport in stratified Nordic coastal seas in the Anthropocene

Elem Sci Anth ◽  
2018 ◽  
Vol 6 ◽  
Author(s):  
Torsten Linders ◽  
Eduardo Infantes ◽  
Alyssa Joyce ◽  
Therese Karlsson ◽  
Helle Ploug ◽  
...  
Keyword(s):  
Coastal Waters ◽  
Interdisciplinary Approach ◽  
Distribution Patterns ◽  
Horizontal Distribution ◽  
Transport Processes ◽  
Bottom Current ◽  
Benthic Boundary Layer ◽  
Retention Capacity ◽  
Run Off ◽  
In Situ Sensors

Particles of all origins (biogenic, lithogenic, as well as anthropogenic) are fundamental components of the coastal ocean and are re-distributed by a wide variety of transport processes at both horizontal and vertical scales. Suspended particles can act as vehicles, as well as carbon and nutrient sources, for microorganisms and zooplankton before eventually settling onto the seafloor where they also provide food to benthic organisms. Different particle aggregation processes, driven by turbulence and particle stickiness, composition, abundance and size, impact the transport and sinking behavior of particles from the surface to the seafloor. In deep coastal waters, the deposition, resuspension, and accumulation of particles are driven by particle stickiness, composition and aggregate structure. In contrast, wave-driven and bottom current-driven processes in the nepheloid benthic boundary layer of shallow waters are of greater importance to the settling behavior of particles, while the retention capacity of benthic vegetation (e.g., seagrasses) further influences particle behavior. In this review, we consider the various processes by which particles are transported, as well as their sources and characteristics, in stratified coastal waters with a focus on Nordic seas. The role of particles in diminishing the quality of coastal waters is increasing in the Anthropocene, as particle loading by rivers and surface run-off includes not only natural particles, but also urban and agricultural particles with sorbed pollutants and contaminants of organic, inorganic and microplastic composition. Human activities such as trawling and dredging increase turbidity and further impact the transport of particles by resuspending particles and influencing their vertical and horizontal distribution patterns. An interdisciplinary approach combining physical, chemical and biological processes will allow us to better understand particle transport and its impact on coastal waters and estuaries at an ecosystem level. There is a need for development of novel analytical and characterization techniques, as well as new in situ sensors to improve our capacity to follow particle dynamics from nanometer to millimeter size scales.

The Run off of Nutrients from Funen, Denmark, and the Consequences for Its Coastal Waters

1991 ◽  
Vol 24 (10) ◽  
pp. 315-318
Author(s):  
J. D. Petersen ◽  
N. Rask ◽  
H. B. Madsen ◽  
S. E. Pedersen
Keyword(s):  
Coastal Waters ◽  
Run Off

scholarly journals Defining and Characterising Clusters in Palaeolithic Sites: a Review of Methods and Constraints

2021 ◽  
Author(s):  
Laura Sánchez-Romero ◽  
Alfonso Benito-Calvo ◽  
Joseba Rios-Garaizar
Keyword(s):  
Distribution Patterns ◽  
Horizontal Distribution ◽  
Spatial Studies ◽  
Innovative Methods ◽  
General Terms ◽  
Fabric Analysis ◽  
Gis Tools ◽  
Definition Of ◽  
Intentional Activities ◽  
Statistical Criteria

AbstractSpatial analysis studies in Palaeolithic archaeology arise as indispensable research tools for understanding archaeopalaeontological sites. In general terms, spatial studies have been specialised in the description of the distribution of materials and in the definition of accumulation areas, with the aim of distinguishing intentional activities or studying postdepositional processes. In recent decades, the development of GIS tools has enabled huge strides forward in the field of spatial archaeology research, such as spatial inferential statistics. These tools are particularly useful in the identification and location of clustering from statistical criteria, facilitating the subsequent analysis of accumulations through other archaeological, taphonomic and spatial techniques, such as fabric analysis or directional distribution. The cluster analysis, and its contextualisation considering all the archaeological and stratigraphical variables, allows the inference of some of the processes and factors that could have taken part in the accumulation of materials, as well as assessing how this affected the composition and preservation of the archaeological assemblage. The present article reviews the more traditional and innovative methods for studying horizontal distribution patterns and the objective definition of clusters, highlighting the parameters, uses and limitations of these techniques. We present an application of these methods to different Palaeolithic sites, going through different scenarios, such as location (open-air vs. cave), context, scale (large vs. small area), excavation methodology and spatial record methods.

scholarly journals STRUKTUR KOMUNITAS DAN ASOSIASI LAMUN (Seagrass) DI PERAIRAN PANTAI RUA PULAU TERNATE PROVINSI MALUKU UTARA

2013 ◽  
Vol 13 (1) ◽  
Author(s):  
Riyadi Subur
Keyword(s):  
Coastal Waters ◽  
Coastal Region ◽  
Positive Association ◽  
Distribution Patterns ◽  
Research Area ◽  
Negative Association ◽  
Line Transect ◽  
Thalassia Hemprichii ◽  
Marine Life ◽  
Cymodocea Rotundata

AbstrakLamun (Seagrass) merupakan salah satu ekosistem penting diwilayah pesisir yangberperan penting baik secara ekologis dan ekonomis. Keberadaan lamun mendukungkehidupan berbagai jenis biota laut. Penelitian ini bertujuan mengidentifikasi jenis-jenislamun yang berada di perairan pantai Rua, Mengetahui kepadatan, pola sebaran,keanekaragaman jenis, dan dominansi serta asosiasi antara spesies. Penelitian ini dilakukandengan metode garis transek dan kuadrat. Hasil penelitian menunjukkan bahwa terdapat 4jenis lamun di perairan pantai Rua yang terdiri dari Cymodocea rotundata, Enhalusacoroides, Halodule pinifolia dan Thalassia hemprichii. T. hemprichii adalah jenis dengankepadatan tertinggi di perairan Rua yaitu 16,70 ind/m2, serta E. acoroides, memilikikepadatan terendah yakni 5,77 ind/m2. Jenis lamun yang ditemukan di lokasi penelitianseluruhnya memiliki pola sebaran mengelompok dengan keanekaragaman yangdikategorikan rendah yaitu sebesar 1,32, serta indeks dominasi sebesar 0,27. Tipe asosiasilamun di lokasi penelitian yaitu asosiasi positif (+), serta asosiasi negatif (-).Kata Kunci. Struktur Komunitas, Asosiasi, lamun.AbstractSeagrass is a important ecosystems coastal region that is important both ecologically andeconomically . The seagrass supports of various marine life. This study to propose identify thespecies of seagrasses in coastal waters in Rua, Knowing the density, distribution pattern,species diversity, and dominance as well as associations between species. This study wasconducted using line transect and kuadrats. The results showed that there are 4 species ofseagrass in Rua consisting of Cymodocea rotundata , Enhalus acoroides , pinifolia Haloduleand Thalassia hemprichii . T. hemprichii is highest density (16.70 ind/m2), and E. acoroides ,which has the lowest density (5.77 ind/m2). Species seagrass found in the research area allhave clumped distribution patterns are categorized with diversity low at 1.32 , and dominanceindex at 0.27. Type association of seagrass in the location studies is positive association ( + )and negative association ( - ).Key Words:community structur, association, seagrass

Coastally trapped waves, baroclinic eddies, internal tides and oceanic fronts at the shelf break: their implications for exchanges between shelf and oceanic waters

1981 ◽  
Vol 302 (1472) ◽  
pp. 661-661 ◽  
Keyword(s):  
Coastal Waters ◽  
Coastal Upwelling ◽  
Shelf Break ◽  
Internal Tides ◽  
Oceanic Fronts ◽  
Run Off ◽  
Break Surface ◽  
Seaward Edge ◽  
Coastally Trapped Waves ◽  
Topographic Rossby Waves

The seaward edge of the continental shelf, or shelf break, is the locus of strong physical variability in the overlying waters. Near the shelf-break, surface tides scatter energy into internal modes that propagate both onshore and offshore and produce strong vertical shears. Atmospheric forcing generates subinertial-frequency topographic Rossby waves, which propagate parallel to the coastline and are strongly trapped near the shelf break. Relative to the sloping topography, wind-driven coastal upwelling generates prograde fronts, and river run-off generates retrograde fronts. Located near the shelf break, these fronts are boundaries between oceanic and coastal waters. Oceanic eddies impinge on, and move along, the shelf-break entraining coastal waters. Eddies may also be shed by shelf-break fronts. Submarine capes and canyons contort the shelf break and significantly modify the enumerated processes. Based on observational evidence from a few coastal regimes, the shelf break is a zone where several mesoscale and synoptic-scale processes operate and probably produce significant turbulent transfers.

scholarly journals Extension of the River Water Quality Model No. 1 with the fate of pesticides

2011 ◽  
Vol 14 (1) ◽  
pp. 48-64 ◽  
Author(s):  
Veerle C. J. De Schepper ◽  
Katrijn M. A. Holvoet ◽  
Lorenzo Benedetti ◽  
Piet Seuntjens ◽  
Peter A. Vanrolleghem
Keyword(s):  
Water Quality ◽  
Water Column ◽  
River Water ◽  
Bulk Water ◽  
Transport Processes ◽  
Water Quality Model ◽  
River Water Quality ◽  
Model Parameters ◽  
Quality Model ◽  
Run Off

The existing River Water Quality Model No. 1 (RWQM1) was extended with processes determining the fate of non-volatile pesticides in the water phase and sediments. The exchange of pesticides between the water column and the sediment is described by three transport processes: diffusion, sedimentation and resuspension. Burial of sediments is also included. The modified model was used to simulate the concentrations of diuron and chloridazon in the river Nil. A good agreement was found between the simulated pesticide concentrations and measured values resulting from a four-month intensive monitoring campaign. The simulation results indicate that pesticide concentrations in the bulk water are not sensitive to the selected biochemical model parameters. It seems that these concentrations are mainly determined by the imposed upstream concentrations, run-off and direct losses. The high concentrations in the bulk water were not observed in the sediment pore water due to a limited exchange between the water column and the sediment. According to a sensitivity analysis, the observed pesticide concentrations are highly sensitive to the diffusion and sorption coefficients. Therefore, model users should determine these parameters with accuracy in order to reduce the degree of uncertainty in their results.

Fate and transport modelling of faecal indicator bacteria in Dublin Bay

2020 ◽  
Author(s):  
Guanghai Gao ◽  
Aisling Corkery ◽  
John O’Sullivan ◽  
Wim Meijer ◽  
Gregory O’Hare ◽  
...  
Keyword(s):  
Water Quality ◽  
Decay Rate ◽  
Coastal Waters ◽  
Transport Processes ◽  
Indicator Bacteria ◽  
Climate Change Scenarios ◽  
Faecal Indicator Bacteria ◽  
Bathing Water ◽  
Intestinal Enterococci ◽  
The Eu

<p>Water-based microbial pathogens are often responsible for the spread of waterborne diseases in polluted coastal waters. However, difficulties in directly measuring pathogens have resulted in Faecal Indicator Bacteria (FIB) being commonly used as risk indicators in coastal and bathing water management. FIB groups, particularly those of E coli and enterococci, are easily quantified in laboratory tests and are used worldwide to assess health risks in bathing and shellfish harvesting waters.</p><p>Dublin Bay off the east coast of Ireland extends to over 300 km<sup>2</sup> and is home to species and habitats of high conservation importance. Its significant environmental, economic, cultural, recreational and tourism importance to the 300,000 people living within the Bay area and to the wider Dublin population is reflected in its 2015 Biosphere designation from the United Nations Educational, Scientific and Cultural Organisation (UNESCO). Recent years however, have seen an increase in pressures on the water quality in Dublin Bay with diffuse and point source pollution discharges from both the urban and rural catchments connected to the bay being a cause of increasing concern for the responsible authorities charged with managing the coastal waters in the context of national and European legislations, particularly the EU Bathing Water Directive (2006/7/EC).</p><p>Here we present the development of a 3-Dimensional numerical model for simulating the transport and fate of FIB (namely E.coli and Intestinal Enterococci) in the receiving waters of Dublin Bay. A dynamic decay rate, which included the effects of salinity, temperature and light intensity was adopted in the model, and was shown to offer advantages over the use of constant decay rate models for simulating the bacterial die-off. More importantly however, the analyses of sediment samples taken from the intertidal zone in the bay revealed relatively high faecal bacteria concentrations. The developed model in this study allows for the effects of sediment on bacteria transport processes in surface waters and in particular, the release of bacteria from sediments into the water column. The model was validated with measurements of current speed and direction at multiple points in Dublin Bay, and with faecal indicator bacteria concentrations (E.coli and Intestinal Enterococci) determined for neap and Spring tides in both wet and dry conditions. Results from model simulations agreed well with observed data. The model represents a high-level strategic tool that will be used to understand how water quality pressures in Dublin Bay may be altered under different climate change scenarios. The work presented forms part of the EU INTERREG funded Acclimatize project (www.acclimatize.eu/) that is investigating the longer-term water quality pressures in Dublin Bay that may arise in the context of a changing climate.</p>

Increased utility of the Secchi disk to assess eutrophication in coastal waters with freshwater run-off

2006 ◽  
Vol 60 (1-2) ◽  
pp. 19-29 ◽  
Author(s):  
Carina P. Erlandsson ◽  
Anders Stigebrandt
Keyword(s):  
Coastal Waters ◽  
Secchi Disk ◽  
Run Off

scholarly journals Horizontal distribution and transport processes of bloom-forming Microcystis in a large shallow lake (Taihu, China)

Limnologica ◽  
2010 ◽  
Vol 40 (1) ◽  
pp. 8-15 ◽  
Author(s):  
Xiaodong Wu ◽  
Fanxiang Kong ◽  
Yuwei Chen ◽  
Xin Qian ◽  
Longjiang Zhang ◽  
...  
Keyword(s):  
Shallow Lake ◽  
Lake Taihu ◽  
Horizontal Distribution ◽  
Transport Processes ◽  
Large Shallow Lake

Detection of mesoscale synoptic features associated with dispersal of spruce budworm moths in eastern Canada

1990 ◽  
Vol 328 (1251) ◽  
pp. 607-617 ◽  
Keyword(s):  
New Brunswick ◽  
Coastal Waters ◽  
Land Surface ◽  
Spruce Budworm ◽  
Distribution Patterns ◽  
Convergence Zone ◽  
Eastern Canada ◽  
Thermal Contrast ◽  
Synoptic Features

Radar studies in eastern Canada of spruce budworm moth distribution patterns and associated windfields frequently revealed mesoscale synoptic features induced by the strong thermal contrast between the heated land surface and the surrounding coastal waters that resulted in significant redistribution of the airborne moths. Experience gained during a four-year study in New Brunswick enabled meteorologists to identify the synoptic situations favouring the development of these mesoscale features. This paper examines the details of a particular case, on 15-16 July 1976, when insect detection teams were alerted in advance to the existence and location of a significant wind convergence zone.

Sign in / Sign up

Export Citation Format

Share Document