scholarly journals The jellyfish buffet: jellyfish enhance seabird foraging opportunities by concentrating prey

2015 ◽  
Vol 11 (8) ◽  
pp. 20150358 ◽  
Author(s):  
Nobuhiko N. Sato ◽  
Nobuo Kokubun ◽  
Takashi Yamamoto ◽  
Yutaka Watanuki ◽  
Alexander S. Kitaysky ◽  
...  
Keyword(s):  
Water Column ◽  
Trophic Level ◽  
Foraging Behaviour ◽  
Marine Ecosystems ◽  
Forage Fish ◽  
Ecological Role ◽  
Marine Predators ◽  
Trophic Pathways ◽  
The World ◽  
Negative Impacts

High levels of jellyfish biomass have been reported in marine ecosystems around the world, but understanding of their ecological role remains in its infancy. Jellyfish are generally thought to have indirect negative impacts on higher trophic-level predators, through changes in lower trophic pathways. However, high densities of jellyfish in the water column may affect the foraging behaviour of marine predators more directly, and the effects may not always be negative. Here, we present novel observations of a diving seabird, the thick-billed murre, feeding on fish aggregating among the long tentacles of large jellyfish, by using small video loggers attached to the birds. We show that the birds encountered large jellyfish, Chrysaora melanaster , during most of their dives, commonly fed on fish associated with jellyfish, and appeared to specifically target jellyfish with a high number of fish aggregating in their tentacles, suggesting the use of jellyfish may provide significant energetic benefits to foraging murres. We conclude that jellyfish provide feeding opportunities for diving seabirds by concentrating forage fish, and that the impacts of jellyfish on marine ecosystems are more complex than previously anticipated and may be beneficial to seabirds.

scholarly journals A Cursory Look at the Fishmeal/Oil Industry From an Ecosystem Perspective

2021 ◽  
Vol 9 ◽  
Author(s):  
Lynne Shannon ◽  
Lauren Waller
Keyword(s):  
South African ◽  
Marine Ecosystem ◽  
Marine Ecosystems ◽  
Forage Fish ◽  
Human Consumption ◽  
Global Context ◽  
Marine Predators ◽  
Cultured Fish ◽  
Increasing Demand

By supporting the fishmeal industry, are we competing with marine predators? Should we be taking away food from marine predators to subsidize agriculture? If not for human consumption, should forage fish be left in the sea for predators? Are there more sustainable alternatives to fishmeal; can the fishing industry be part of developing these? These are all pressing questions being posed by marine scientists, particularly in the light of the increasing aquaculture industry and associated increasing demand in recent decades for fishmeal and oil to sustain cultured fish. We concisely summarize the global context of marine sourced fishmeal and then use the South African marine ecosystem as a working example. This article draws on research into the trophic role of forage fish in marine ecosystems and ponders whether a reduced demand for fishmeal, given increasing global pressures such as climate change, could benefit marine ecosystems, fisheries on predatory species, and vulnerable marine predators.

scholarly journals Responses of lower trophic-level organisms to typhoon passage on the outer shelf of the East China Sea: an incubation experiment

2013 ◽  
Vol 10 (4) ◽  
pp. 6605-6635 ◽  
Author(s):  
N. Yasuki ◽  
K. Suzuki ◽  
A. Tsuda
Keyword(s):  
Water Column ◽  
East China Sea ◽  
Trophic Level ◽  
Outer Shelf ◽  
East China ◽  
Strong Wind ◽  
The East China Sea ◽  
Phytoplankton Productivity ◽  
China Sea ◽  
Lower Trophic Level

Abstract. Typhoons can induce vertical mixing, upwelling, or both in the water column due to strong wind stress. These events can induce phytoplankton blooms in the oligotrophic ocean after typhoon passage. However, little is known about the responses of lower trophic-level organisms or changes in the community structure following the passage of typhoons, particularly in offshore regions. Therefore, we evaluated community succession on the outer shelf of the East China Sea through on-deck bottle incubation experiments simulating hydrographic conditions after the passage of a typhoon. Under all of the experimental conditions we tested, chlorophyll a concentrations increased more than 9-fold within 6 days, and these algal cells were mainly composed of large diatoms (>10 μm). Ciliates also increased along with the diatom bloom. These results suggest that increases in diatom and ciliate populations may enhance biogenic carbon export in the water column. Typhoons can affect not only phytoplankton productivity, but also the composition of lower trophic-level organisms and biogeochemical processes in oligotrophic offshore regions.

Trends in phytoplankton communities within large marine ecosystems diverge from the global ocean

2021 ◽  
pp. 1-12
Author(s):  
Kevin D. Friedland ◽  
John R. Moisan ◽  
Aurore A. Maureaud ◽  
Damian C. Brady ◽  
Andrew J. Davies ◽  
...  
Keyword(s):  
Chlorophyll Concentration ◽  
World Ocean ◽  
Marine Ecosystems ◽  
Fishing Effort ◽  
Global Ocean ◽  
Human Populations ◽  
Anthropogenic Pressures ◽  
Large Marine Ecosystems ◽  
Phytoplankton Communities ◽  
The World

Large marine ecosystems (LMEs) are highly productive regions of the world ocean under anthropogenic pressures; we analyzed trends in sea surface temperature (SST), cloud fraction (CF), and chlorophyll concentration (CHL) over the period 1998–2019. Trends in these parameters within LMEs diverged from the world ocean. SST and CF inside LMEs increased at greater rates inside LMEs, whereas CHL decreased at a greater rates. CHL declined in 86% of all LMEs and of those trends, 70% were statistically significant. Complementary analyses suggest phytoplankton functional types within LMEs have also diverged from those characteristic of the world ocean, most notably, the contribution of diatoms and dinoflagellates, which have declined within LMEs. LMEs appear to be warming rapidly and receiving less solar radiation than the world ocean, which may be contributing to changes at the base of the food chain. Despite increased fishing effort, fishery yields in LMEs have not increased, pointing to limitations related to productivity. These changes raise concerns over the stability of these ecosystems and their continued ability to support services to human populations.

scholarly journals Space time evolution of the trophic state of a subtropical lagoon: Lagoa da Conceição, Florianópolis Island of Santa Catarina, Brazil

RBRH ◽  
2017 ◽  
Vol 22 (0) ◽  
Author(s):  
Victor Eduardo Cury Silva ◽  
Davide Franco ◽  
Alessandra Larissa Fonseca ◽  
Maria Luiza Fontes ◽  
Alejandro Rodolfo Donnangelo
Keyword(s):  
Water Column ◽  
Trophic Level ◽  
Algal Blooms ◽  
Trophic State ◽  
Coastal Lagoons ◽  
Principal Component ◽  
Quality Data ◽  
Santa Catarina ◽  
Water Quality Data ◽  
Subtropical Lagoon

ABSTRACT High levels of eutrophication in coastal lagoons due to human activity have been documented worldwide. Among the main impacts observed are anoxia, hypoxia, toxic algal blooms, fish kills, loss of biodiversity and loss of bathing. This study aimed to evaluate the evolution of the trophic state of Lagoa da Conceição, a subtropical lagoon located in an urbanized watershed on the island of Santa Catarina - Brazil. Spatio temporal patterns of stratification and eutrophication were investigated to understand the main biochemical changes over time. The water quality data were obtained from field campaigns supplemented with literature of the last 15 years. The vertical structure of the water column and the trophic state were evaluated by the stratification index and the TRIX index, respectively. Analyses of variance were performed in order to identify possible temporal variations in vertical stratification and trophic level. Eutrophication effects on biogeochemical cycles were verified through a multi-dimensional cluster analysis (MDS) and correlations between variables related to physical, chemical and biological processes were verified by principal component analysis (PCA). The results showed that the water column is homogeneous in all regions except in the central region of the lagoon, and the highest ammonia concentrations and lowest dissolved oxygen concentrations with periods of anoxia are observed in bottom waters. The study looked at the high trophic level of the lagoon and its inability to process the biogeochemical changes imposed by urban development.

scholarly journals BRIOZOOS CHEILOSTOMADOS DEL CARIBE COLOMBIANO

2016 ◽  
Vol 35 ◽  
Author(s):  
Paola Flórez Romero ◽  
Erika Montoya Cadavid ◽  
Javier Reyes Forero ◽  
Nadiezhda Santodomingo
Keyword(s):  
Continental Shelf ◽  
Marine Ecosystems ◽  
Soft Bottom ◽  
Marine Fauna ◽  
Geographic Ranges ◽  
The World ◽  
Growth Types ◽  
Soft Bottoms ◽  
Upper Slope

The Cheilostomes are the most diverse existent bryozoans group. Its species are commonly found in all the marine ecosystems around the world. In Colombia, however, information about them is scarce and limited to few localities. With the initiative of exploring the soft bottom biodiversity and completing the Colombian marine fauna inventories, INVEMAR-Macrofauna II exploration took place in March 2001, during which samples were collected on soft bottoms throughout the Colombian Caribbean from the continental shelf and the upper slope (20 – 500 m depth) by trawling. 62 species of Cheilostomes that belong to 39 families were found, 36 are first records for the Colombian Caribbean, 4 for the Great Caribbean and 1 for the Tropical West Atlantic. Bathymetric and geographic ranges are extended for 13 species. Taxonomical notes and images of the five species that are first records for the Greater Caribbean and the Tropical West Atlantic are included in this survey. It also includes remarks about the distribution, substrata, and growth types of Cheilostomata studied.

scholarly journals Higher Education Students and Covid-19: Challenges and Strategies in facing Online Learning

2021 ◽  
Vol 10 (3) ◽  
pp. 396
Author(s):  
Anang Fathoni ◽  
Ali Mustadi ◽  
Wahyu Kurniawati
Keyword(s):  
Higher Education ◽  
Online Learning ◽  
Data Analysis ◽  
Significant Influence ◽  
Learning Strategy ◽  
Learning Activities ◽  
Education Students ◽  
Integration Of Technology ◽  
The World ◽  
Negative Impacts

The emergence of Covid-19 has had a significant influence on the world of education. Even though the emergence of Covid-19 has accelerated the integration of technology in learning, there are still negative classroom learning impacts. This study aims to explore student experience in online learning in the Covid-19 Pandemic period; describe the negative impacts and obstacles that arise in online learning; and describe student strategies in online learning. This research is qualitative in the type of case studies. Data were collected through open questionnaires and interviews with participants of 20 students. Data analysis was accomplished with Bogdan and Biklen models through reduction, searching for sub-themes, and seeking relationships between sub-themes to obtain the conclusion. The results of this study show that learning in the Covid-19 pandemic period has not been fully optimally done. In addition, students also get physical and mental impacts during online learning. Furthermore, students get barriers to signals, learning environment, and learning activities with lecturers online. However, students have a varied learning strategy to minimize obstacles and negative impacts of online learning.

scholarly journals Educational Philosophy in the Effect of Globalization on Agriculture

2020 ◽  
Vol 1 (1) ◽  
pp. 7-10
Author(s):  
Aslan Riyadh
Keyword(s):  
Educational Philosophy ◽  
Agricultural Sector ◽  
The Public ◽  
Technology Sector ◽  
Technological Advances ◽  
The World ◽  
Rapid Flow ◽  
Vertical Relationship ◽  
Negative Impacts

Technological advances due to the rapid flow of globalization, change the pattern of teaching in the world of education. The philosophy of education shows a vertical relationship, up or down with the branches of education. It is hoped that the public can better understand the importance of globalization so that the negative impacts that have an impact can be minimized and it is also hoped that the realization of positive activities towards education will be even better. Education contributing to the success of development in the agricultural sector is not solely determined by development in the technology sector but is determined by the development of the quality of human resources, aspects of human personality, which include knowledge, values, attitudes and skills. The influence of globalization encourages education in the agricultural sector to be increasingly encouraged by stakeholders to always be improved so that the agricultural sector becomes more productive.

scholarly journals InBUy database of Invasive and Alien Species (IAS) in Uruguay: a useful tool to confront this threat to biodiversity

2010 ◽  
Vol 10 (4) ◽  
pp. 205-213 ◽  
Author(s):  
Silvana Masciadri ◽  
Ernesto Brugnoli ◽  
Pablo Muniz
Keyword(s):  
Vascular Plants ◽  
Prevention And Control ◽  
Life Forms ◽  
The World ◽  
Time Periods ◽  
Negative Impacts ◽  
Managed Ecosystems ◽  
Taxonomic Groups ◽  
And Control ◽  
Trees And Shrubs

In Uruguay, as well as in other regions of the world, IAS cause negative impacts on natural and managed ecosystems. The use of databases is a helpful tool to elaborate different strategies for prevention and control, and to develop policies and scientific analyses related to IAS. The database of IAS in Uruguay (InBUy) was developed during two time periods (2006-2007 and 2009-2010). It currently contains information on 33 specialists of different taxonomic groups, 14 research projects, 185 references, 351 species and 4,715 records, with vascular plants having both the highest number of species and records. Among vascular plants, herbaceous life forms are the most strongly represented, followed by trees and shrubs. Within animals, the fishes and mollusks are the most important groups. Analysis of the native distribution areas of IAS showed that most are indigenous from Europe, followed by Asia and Oceania. Data showed that introductions of IAS into Uruguay are mainly intentional (67%), so efforts should be focused on policies and rules in order to control the entrance of exotic organisms and prevent new invasions. The geography of the compiled dataset shows the main impact is along the coastline, where the highest exotic species richness and records occurs, and also the most biological invasions. The InBUy database is up-to-date and has successfully contributed to the creation of an official IAS list for Uruguay and both a National and a Coastal Geographic Information System. It has also been used for developing consciousness about this important threat to biodiversity, at both national and regional scales.

Akuisisi Bukti Digital Viber Messenger Android Menggunakan Metode National Institute of Standards and Technology (NIST)

2021 ◽  
Vol 5 (1) ◽  
pp. 45-54
Author(s):  
Imam Riadi ◽  
Rusydi Umar ◽  
Muhammad Irwan Syahib
Keyword(s):  
Extraction Process ◽  
Text Messages ◽  
Digital Evidence ◽  
Digital Forensic ◽  
Digital Crime ◽  
The World ◽  
Instant Messenger ◽  
Negative Impacts ◽  
Forensic Tools ◽  
Voice Calls

Viber is one of the most popular social media in the Instant Messenger application category that can be used to send text messages, make voice calls, send picture messages and video messages to other users. As many as 260 million people around the world have used this application. Increasing the number of viber users certainly brings positive and negative impacts, one of the negative impacts of this application is the use of digital forensic crime. This research simulates and removes digital crime evidence from the viber application on Android smartphones using the National Institute of Standards Technology (NIST) method, which is a method that has work guidelines on forensic policy and process standards to ensure each investigator follows the workflow the same so that their work is documented and the results can be accounted for. This study uses three forensic tools, MOBILedit Forensic Express, Belkasoft and Autopsy. The results in this study show that MOBILedit Forensic Express gets digital evidence with a percentage of 100% in getting accounts, contacts, pictures and videos. While proof of digital chat is only 50%. Belkasoft gets digital evidence with a percentage of 100% in getting accounts, contacts, pictures and videos. While proof of digital chat is only 50%. For Autopsy does not give the expected results in the extraction process, in other words the Autopsy application gives zero results. It can be concluded that MOBILedit Forensic Express and Belkasoft have a good performance compared to Autopsy and thus this research has been completed and succeeded in accordance with the expected goals.

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