scholarly journals Short-term fate of seagrass and macroalgal detritus in Arenicola marina bioturbated sediments

2020 ◽  
Vol 639 ◽  
pp. 21-35
Author(s):  
ACG Thomson ◽  
E Kristensen ◽  
T Valdemarsen ◽  
CO Quintana
Keyword(s):  
Zostera Marina ◽  
Benthic Fauna ◽  
C Sequestration ◽  
Fucus Vesiculosus ◽  
Short Term ◽  
Arenicola Marina ◽  
Seagrass Meadows ◽  
Seagrass Ecosystems ◽  
The Common ◽  
Discrete Layer

Seagrass meadows are globally important ecosystems for carbon (C) sequestration. However, bioturbation by benthic fauna can alter the distribution, degradation and overall preservation of C in the sediment. We performed a 4 wk laboratory experiment to investigate the short-term degradation and burial of 2 major C sources in bare sediments associated with seagrass ecosystems. Eelgrass Zostera marina and macroalgal (Fucus vesiculosus) detritus were amended in sediment with and without bioturbation by the common polychaete Arenicola marina. Bioturbation did not significantly affect the loss of eelgrass detritus (>0.5 mm), but caused a rapid burial of this material as a discrete layer (55% recovery) at sediment depths ranging from 8 to 14 cm. A. marina effects on macroalgal detritus were more pronounced, resulting, in total, in an 80% loss of macroalgal detritus by microbial degradation and worm ingestion. We conclude that A. marina bioturbation effectively buries eelgrass detritus into deep anoxic sediments, but we cannot confirm that this leads to enhanced C preservation in coastal ecosystems. In contrast, A. marina bioturbation significantly increases the degradation of macroalgal tissue, and it is unlikely that this detritus is a major source for permanent C burial.

scholarly journals Are complications of endoscopic sphincterotomy age related?

Gut ◽  
1997 ◽  
Vol 41 (4) ◽  
pp. 545-548 ◽  
Author(s):  
G T Deans ◽  
P Sedman ◽  
D F Martin ◽  
C M S Royston ◽  
C K Leow ◽  
...  
Keyword(s):  
Laparoscopic Cholecystectomy ◽  
Endoscopic Sphincterotomy ◽  
Short Term ◽  
Endoscopic Retrograde ◽  
Younger Patients ◽  
Age Related ◽  
Increased Risk ◽  
Ascending Cholangitis ◽  
Retroperitoneal Perforation ◽  
The Common

Background—Endoscopic retrograde cholangiopancreatography sphincterotomy is increasingly performed in younger patients undergoing laparoscopic cholecystectomy. However, the safety of endo- scopic sphincterotomy in this age group, relative to that in older patients, is unknown.Aim—To determine whether the development of short term complications following endoscopic sphincterotomy is age related.Patients and methods—A prospective multicentre audit of 958 patients (mean age 73, range 14–97, years) undergoing a total of 1000 endoscopic sphincterotomies.Results—Two deaths occurred, both from postsphincterotomy acute pancreatitis. Postprocedural complications developed in 24 patients: pancreatitis in 10, ascending cholangitis in seven, bleeding in four, and retroperitoneal perforation in three. There were six complications (five cases of pancreatitis and one bleed; 2.2%) and no deaths in the 281 (29.3%) patients aged under 65 years. In comparison, 18 (2.6%) of the 677 patients aged over 65 years developed a complication (cholangitis in seven, pancreatitis in five, bleeding in three, and perforation in three). Patients under 35, 45, 55, and 65 years were not at significantly increased risk of complication than those over these ages (relative risk for those under compared with those over 65 years 0.83, 95% confidence intervals 0.41–1.67, p=0.74).Conclusion—Short term complications following endoscopic sphincterotomy are not related to age. Younger patients undergoing laparoscopic cholecystectomy need not be denied endoscopic sphincterotomy for fear that the risks are greater than if they undergo surgical exploration of the common bile duct.

Unoccupied aerial vehicle-assisted monitoring of benthic vegetation in the coastal zone enhances the quality of ecological data

2021 ◽  
pp. 030913332110520
Author(s):  
Niels Svane ◽  
Troels Lange ◽  
Sara Egemose ◽  
Oliver Dalby ◽  
Aris Thomasberger ◽  
...  
Keyword(s):  
Zostera Marina ◽  
Spatial Scales ◽  
Fucus Vesiculosus ◽  
Ecosystem Dynamics ◽  
Spatial Extent ◽  
Total Biomass ◽  
Ecological Data ◽  
Error Matrix ◽  
Object Based ◽  
Spatio Temporal

Traditional monitoring (e.g., in-water based surveys) of eelgrass meadows and perennial macroalgae in coastal areas is time and labor intensive, requires extensive equipment, and the collected data has a low temporal resolution. Further, divers and Remotely Operated Vehicles (ROVs) have a low spatial extent that cover small fractions of full systems. The inherent heterogeneity of eelgrass meadows and macroalgae assemblages in these coastal systems makes interpolation and extrapolation of observations complicated and, as such, methods to collect data on larger spatial scales whilst retaining high spatial resolution is required to guide management. Recently, the utilization of Unoccupied Aerial Vehicles (UAVs) has gained popularity in ecological sciences due to their ability to rapidly collect large amounts of area-based and georeferenced data, making it possible to monitor the spatial extent and status of SAV communities with limited equipment requirements compared to ROVs or diver surveys. This paper is focused on the increased value provided by UAV-based, data collection (visual/Red Green Blue imagery) and Object Based Image Analysis for gaining an improved understanding of eelgrass recovery. It is demonstrated that delineation and classification of two species of SAV ( Fucus vesiculosus and Zostera marina) is possible; with an error matrix indicating 86–92% accuracy. Classified maps also highlighted the increasing biomass and areal coverage of F. vesiculosus as a potential stressor to eelgrass meadows. Further, authors derive a statistically significant conversion of percentage cover to biomass ( R2 = 0.96 for Fucus vesiculosus, R2 = 0.89 for Zostera marina total biomass, and R2 = 0.94 for AGB alone, p < 0.001). Results here provide an example of mapping cover and biomass of SAV and provide a tool to undertake spatio-temporal analyses to enhance the understanding of eelgrass ecosystem dynamics.

Seagrass Ecosystems of Andaman and Nicobar Islands: Status and Future Perspective

2020 ◽  
Vol 7 (4) ◽  
pp. 169-174
Author(s):  
Chatragadda Ramesh ◽  
Raju Mohanraju
Keyword(s):  
Water Quality ◽  
Primary Production ◽  
Environmental Changes ◽  
Future Perspective ◽  
Marine Biodiversity ◽  
Seagrass Beds ◽  
Seagrass Meadows ◽  
Seagrass Ecosystem ◽  
Seagrass Ecosystems ◽  
Nicobar Islands

Seagrasses are unique marine flowering plants that play an important ecological role by yielding primary production and carbon sequestration to the marine environment. Seagrass ecosystems are rich in organic matter, supporting the growth of bio-medically important epi and endophytic microorganisms and harbor rich marine biodiversity. They are an essential food source for endangered Andaman state animal Dugongs. Seagrasses are very sensitive to water quality changes, and therefore they serve as ecological bio-indicators for environmental changes. The benthic components in and around the seagrass beds support a significant food chain for other Micro and organisms apart from fishery resources. The epiphytic bacterial communities of the leaf blades support the sustenance against the diseases. Recent reports have shown that the loss of seagrass beds in tropical and temperate regions emphasizes the depletion of these resources, and proper management of seagrass is urgent. The decline of seagrass will impact primary production, biodiversity, and adjacent ecosystems, such as reefs. Therefore, restoring the seagrass meadows could be possible with effective implementing management programs, including seagrass meadows in marine protected areas, restoration projects, seagrass transplantation, implementation of legislative rules, monitoring coastal water quality and human activities in the coastal zone. Lacunas on the seagrass ecosystem management in Andaman & Nicobar Islands are addressed.

Photosynthetic and metabolic responses of eelgrass Zostera marina L. to short-term high-temperature exposure

2018 ◽  
Vol 37 (1) ◽  
pp. 199-209
Author(s):  
Yaping Gao ◽  
Zengjie Jiang ◽  
Meirong Du ◽  
Jinghui Fang ◽  
Weiwei Jiang ◽  
...  
Keyword(s):  
High Temperature ◽  
Zostera Marina ◽  
Metabolic Responses ◽  
Short Term ◽  
High Temperature Exposure ◽  
Temperature Exposure

scholarly journals Symbol Grounding Association in Multimodal Sequences with Missing Elements

2018 ◽  
Vol 61 ◽  
pp. 787-806
Author(s):  
Federico Raue ◽  
Andreas Dengel ◽  
Thomas M. Breuel ◽  
Marcus Liwicki
Keyword(s):  
Dynamic Time Warping ◽  
Learning Rule ◽  
Abstract Concepts ◽  
Time Warping ◽  
Short Term ◽  
Recent Approach ◽  
Extra Step ◽  
The Common ◽  
Dynamic Time ◽  
General Scope

In this paper, we extend a symbolic association framework for being able to handle missing elements in multimodal sequences. The general scope of the work is the symbolic associations of object-word mappings as it happens in language development in infants. In other words, two different representations of the same abstract concepts can associate in both directions. This scenario has been long interested in Artificial Intelligence, Psychology, and Neuroscience. In this work, we extend a recent approach for multimodal sequences (visual and audio) to also cope with missing elements in one or both modalities. Our method uses two parallel Long Short-Term Memories (LSTMs) with a learning rule based on EM-algorithm. It aligns both LSTM outputs via Dynamic Time Warping (DTW). We propose to include an extra step for the combination with the max operation for exploiting the common elements between both sequences. The motivation behind is that the combination acts as a condition selector for choosing the best representation from both LSTMs. We evaluated the proposed extension in the following scenarios: missing elements in one modality (visual or audio) and missing elements in both modalities (visual and sound). The performance of our extension reaches better results than the original model and similar results to individual LSTM trained in each modality.

scholarly journals STRUKTUR KOMUNITAS IKAN PADA EKOSISTEM LAMUN DI PANTAI PUDING KABUPATEN BANGKA SELATAN

2018 ◽  
Vol 12 (2) ◽  
pp. 35-44
Author(s):  
Sania Prisilia ◽  
Wahyu Adi ◽  
Arief Febrianto
Keyword(s):  
Strong Relationship ◽  
Data Retrieval ◽  
Line Transect ◽  
Thalassia Hemprichii ◽  
Seagrass Meadows ◽  
Gill Net ◽  
Seagrass Ecosystems ◽  
Halodule Uninervis ◽  
Relationship Of ◽  
Seagrass Density

Seagrass beds have a variety of roles in fish life, which can be used as nurseries, as a place for feeding ground, and for areas to seek protection. This study aims to analyze the structure of fish communities and seagrass communities and analyze the relationship of fish abundance with seagrass ecosystems. This research was conducted in March 2018 on the beach of Puding Air Banten II, Pasir Putih Village, Tukak Sadai District, Bangka Selatan Regency. Line transect method for seagrass data collection and fish data retrieval using fixed gill nets (gill net). The results of the study found that the total number of individual fish as much as 409 ind / m2 consisted of 25 species. The highest abundance of fish found in Station I with Ambassis interrupta species as many as 241 ind / m2. There were six types of seagrass found on the coast of Puding, namely Enhalus acoroides, Thalassia hemprichii, Halodule uninervis, Halophila spinulosa, Halophila decipiens and Cymodocea serrulata. The highest seagrass density was found at Station I with the seagrass Halodule uninervis species of 2541 ind / m2. Correlation coefficient analysis shows that the abundance of fish with seagrass density has a significant value of 0.956 which is classified as having a very strong relationship. Fish have higher abundance with seagrass meadows which vegetate with mangroves

scholarly journals Alternative Sanctions in the Gap Between the Law and Reality / Alternativne sankcije u raskoraku između normativnog i stvarnog

2015 ◽  
Vol 5 (5) ◽  
pp. 124
Author(s):  
Veljko Ikanović
Keyword(s):  
Bosnia And Herzegovina ◽  
Common Good ◽  
Prison Sentence ◽  
Electronic Surveillance ◽  
Short Term ◽  
House Arrest ◽  
International Obligations ◽  
The Common ◽  
Criminal Legislation ◽  
Alternative Sanctions

This paper deals with some alternative sanctions of the criminal legislation in Bosnia and Herzegovina. Author pays attention to, first of all, replacing short-term imprisonment with the common good in freedom and house arrest with electronic surveillance, which was recently introduced in the Federation of Bosnia and Herzegovina, and the replacement of short-term prison sentence with a fine. Pointing out the scientific understanding of the need for the development and introduction of alternative sanctions and binding international documents, he examines the limitations of the existing legal desicions, the legislator notes inertia and resistance to general and political public for the legal solutions to be implemented in life. Finally,  in the conclusion he says that there is a gap between law and reality that threatens the goal and purpose of alternative sanctions and also the fulfillment of international obligations which Bosnia and Herzegovina has taken in this area.

Carbon storage in seagrass ecosystems along the Andaman coast of Thailand

2018 ◽  
Vol 61 (5) ◽  
pp. 429-440 ◽  
Author(s):  
Milica Stankovic ◽  
Naruemon Tantipisanuh ◽  
Anchana Prathep
Keyword(s):  
Climate Change ◽  
Carbon Content ◽  
Carbon Storage ◽  
Significant Influence ◽  
West Coast ◽  
Human Disturbance ◽  
Total Carbon ◽  
The West ◽  
Seagrass Meadows ◽  
Seagrass Ecosystems

Abstract Seagrass ecosystems are important contributors to mitigation of climate change, since they are responsible for large carbon sinks. However, there is limited knowledge regarding the importance of variability of carbon storage in various ecosystems. In this study, we estimated carbon storage in several structurally different seagrass meadows along the west coast of Thailand and determined whether degree of exposure, human disturbance, and meadow type influenced carbon storage within these meadows. Carbon content within the living vegetation was on average 3±2.7 Mg ha−1, whilst average storage of carbon in the sediment was 122±35.3 Mg ha−1. Meadow type and disturbance had a significant influence on total carbon storage in the ecosystem, while the degree of exposure of the bay did not show great differences. Uniform meadows had a higher average total carbon storage than mixed meadows (133±36.2 and 110±41.3 Mg ha−1, respectively). Undisturbed meadows had a higher average total carbon storage than disturbed ones (140±36.5 and 103±34.8 Mg ha−1, respectively). The results obtained contribute to our understanding of carbon storage on an ecosystem scale and can provide a baseline for proper management, conservation, and climate change studies in the region.

Ewolucja bezpieczeństwa energetycznego Polski i Białorusi na międzynarodowym rynku ropy naftowej

2021 ◽  
Vol 19 (1) ◽  
pp. 121-139
Author(s):  
Maciej Mróz
Keyword(s):  
Crude Oil ◽  
Energy Policy ◽  
Energy Security ◽  
Political Instability ◽  
Building Energy ◽  
Energy Resources ◽  
Modern World ◽  
Short Term ◽  
Diversification Strategy ◽  
The Common

Access to energy resources has become one of the main challenges of energy security in the modern world. Due to the growing political instability of countries exporting energy resources, the energy security category should be perceived in a special way. Energy security is expressed, first of all, in stable access to energy resources at an acceptable price. The aim of the article is to determine to what extent the strategy of diversifying the sources of crude oil imports to Poland and Belarus is implemented in practice, and to what extent the implementation of this strategy is conducive to building energy security for both these countries. It seems that despite the similar geological and geographical conditions, as well as the common historical infrastructure heritage, Poland and Belarus shape their energy policy differently. The conducted analysis has an empirical dimension, as the REES index is used to measure the concentration of imports and the short-term risk for the security of crude oil supplies. The article shows that a properly implemented diversification strategy significantly improves the country’s energy security, which is possible due to the use of alternative directions for oil imports to the Russian one.

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