Contoured Vertical Distribution and Spatio-temporal Variation of an Intertidal Macroalgal Assemblage in King George Island, Antarctica

Abstract Short-term variability, spatial variability, and the vertical distribution of an intertidal macroalgal assemblage were examined on the coast of Barton Peninsula, Maxwell Bay, King George Island, Antarctica. Sampling was performed during the three austral summer seasons from November 2016 to January 2019. The sampling interval for short-term variability was 1–2 months. Sampling for spatial variability was performed at two sites 400 m apart. Eighteen algal species were identified, with 75% relative coverage of the predominant red Iridaea cordata and endemic brown Phaeurus antarcticus. Summer abundance can be described as a shift from I. cordata to P. antarcticus, and the change in color is intuitively presented using a contour plot for the first time. Short-term variation in the macroalgal assemblage showed 78.35% similarity between one month and 64.61% similarity between two months. The spatial variation analysis indicated 77.13% similarity between the assemblage at the two sites. If global warming continues, the algal population of this region is expected to expand. P. antarcticus, which is primarily found in the subtidal zone, is predicted to relocate southward or higher in the near future. Long-term monitoring of this research region, which is dominated by the two species, is warranted to determine the impact of global warming on the macroalgal assemblage.

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Fetal Vibroacoustic Stimulation in Computerized Cardiotocographic Analysis: The Role of Short-Term Variability and Approximate Entropy

Journal of Pregnancy ◽

10.1155/2012/814987 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

Maria Laura Annunziata ◽

Mariamaddalena Scala ◽

Natascia Giuliano ◽

Salvatore Tagliaferri ◽

Olga Carmela Maria Imperato ◽

...

Keyword(s):

High Risk ◽

Perinatal Outcomes ◽

Approximate Entropy ◽

Computer Assisted ◽

Short Term ◽

Fetal Movements ◽

The Impact ◽

Short Term Variability

The aim of this study was to evaluate the impact of vibroacoustic stimulation (VAS) on computerized cardiotocography short-term variability (STV) and approximate entropy (ApEn) in both low- and high-risk pregnancies. VAS was performed on 121 high- and 95 low-risk pregnancies after 10 minutes of continuous quiet, while their FHR parameters were monitored and recorded by cCTG analysis. Fetal heart rate was recorded using a computer-assisted equipment. Baseline FHR, accelerations, decelerations, STV, long-term irregularity (LTI), ApEn, and fetal movements (FMs) were calculated for defined observational periods before VAS and after 10 minutes. Data were also investigated in relationship with the perinatal outcome. In each group of patients, FHR after VAS remained almost unmodified. Fetal movements significantly increased after VAS in both groups. Results show that only in the high-risk pregnancies, the increase of STV and the decrease of ApEn after VAS were significantly associated with favorable perinatal outcomes.

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The impact of DC/AC ratio on short-term variability of utility-scale PV plants

2019 IEEE Power & Energy Society General Meeting (PESGM) ◽

10.1109/pesgm40551.2019.8974081 ◽

2019 ◽

Author(s):

Kanyawee Keeratimahat ◽

Anna Bruce ◽

Iain MacGill

Keyword(s):

Short Term ◽

Utility Scale ◽

The Impact ◽

Short Term Variability

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Comparison of Short-Term Toxicity of 14 Common Phycotoxins (Alone and in Combination) To The Survival of Brine Shrimp Artemia Salina

10.21203/rs.3.rs-905984/v1 ◽

2021 ◽

Author(s):

Yu Ting Zhang ◽

Shanshan SONG ◽

Bin ZHANG ◽

Yang ZHANG ◽

Miao TIAN ◽

...

Keyword(s):

Ecological Risk ◽

Harmful Algal Blooms ◽

Algal Blooms ◽

Algal Species ◽

Natural Populations ◽

Marine Ecosystems ◽

Artemia Salina ◽

Marine Organisms ◽

Short Term ◽

The Impact

Abstract Toxic harmful algal blooms (HABs) can cause deleterious effects in marine organisms, threatening the stability of marine ecosystems. It is well known that different strains, natural populations and growth conditions of the same toxic algal species may lead to different amount of phycotoxin production and the ensuing toxicity. To fully assess the ecological risk of toxic HABs, it is of great importance to investigate the toxic effects of phycotoxins in marine organisms. In this study, the short-term toxicity of 14 common phycotoxins (alone and in combination) in the marine zooplankton Artemia salina was investigated. On the basis of 48 h LC50, the order of toxicity in A. salina was AZA3 (with a LC50 of 0.0203 µg/ml)＞AZA2 (0.0273 µg/ml) ＞PTX2 (0.0396 µg/ml)＞DTX1 (0.0819 µg/ml)＞AZA1 (0.106 µg/ml)＞ SPX1 (0.144 µg/ml)＞YTX (0.172 µg/ml)＞dcSTX (0.668 µg/ml)＞OA (0.728 µg/ml)＞STX (1.042 µg/ml)＞GYM (1.069 µg/ml)＞PbTx3 (1.239 µg/ml)＞hYTX (1.799 µg/ml)＞PbTx2 (2.415 µg/ml). For the binary exposure, additive effects of OA and DTX1, DTX1 and hYTX; antagonistic effects of OA and PTX2, OA and STX; and synergetic effects of DTX1 and STX, DTX1 and YTX, DTX1 and PTX2, PTX2 and hYTX on the mortality of A. salina were observed. These results provide valuable toxicological data for assessing the impact of phycotoxins on marine planktonic species and highlight the potential ecological risk of toxic HABs in marine ecosystems.

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Quantifying the impact of emission outbursts and non-stationary flow on eddy-covariance CH<sub>4</sub> flux measurements using wavelet techniques

Biogeosciences ◽

10.5194/bg-16-3113-2019 ◽

2019 ◽

Vol 16 (16) ◽

pp. 3113-3131 ◽

Cited By ~ 3

Author(s):

Mathias Göckede ◽

Fanny Kittler ◽

Carsten Schaller

Keyword(s):

Eddy Covariance ◽

Methane Flux ◽

Stationary Flow ◽

Methane Emissions ◽

Gap Filling ◽

Short Term ◽

Flux Measurements ◽

Systematic Biases ◽

The Impact ◽

Short Term Variability

Abstract. Methane flux measurements by the eddy-covariance technique are subject to large uncertainties, particularly linked to the partly highly intermittent nature of methane emissions. Outbursts of high methane emissions, termed event fluxes, hold the potential to introduce systematic biases into derived methane budgets, since under such conditions the assumption of stationarity of the flow is violated. In this study, we investigate the net impact of this effect by comparing eddy-covariance fluxes against a wavelet-derived reference that is not negatively influenced by non-stationarity. Our results demonstrate that methane emission events influenced 3 %–4 % of the flux measurements and did not lead to systematic biases in methane budgets for the analyzed summer season; however, the presence of events substantially increased uncertainties in short-term flux rates. The wavelet results provided an excellent reference to evaluate the performance of three different gap-filling approaches for eddy-covariance methane fluxes, and we show that none of them could reproduce the range of observed flux rates. The integrated performance of the gap-filling methods for the longer-term dataset varied between the two eddy-covariance towers involved in this study, and we show that gap-filling remains a large source of uncertainty linked to limited insights into the mechanisms governing the short-term variability in methane emissions. With the capability for broadening our observational methane flux database to a wider range of conditions, including the direct resolution of short-term variability on the order of minutes, wavelet-derived fluxes hold the potential to generate new insight into methane exchange processes with the atmosphere and therefore also improve our understanding of the underlying processes.

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SHORT-TERM VARIABILITY OF COASTAL ZONE HYDRODYNAMICS UNDER AN EXTERNAL FORCING: OBSERVATIONS AT THE BLACK SEA RESEARCH SITE OF SIO RAS

Proceedings of International Conference "Managinag risks to coastal regions and communities in a changinag world" (EMECS'11 - SeaCoasts XXVI) ◽

10.21610/conferencearticle_58b4315a048a4 ◽

2017 ◽

Author(s):

Andrey Zatsepin ◽

Sergey Kuklev ◽

Alexander Ostrovskii ◽

...

Keyword(s):

Coastal Zone ◽

The Black Sea ◽

External Forcing ◽

Short Term ◽

Shirshov Institute ◽

Open Sea ◽

Observational Site ◽

Upper Mixed Layer ◽

The Impact ◽

Short Term Variability

Since 2010, the P.P. Shirshov Institute of Oceanology RAS (SIO RAS) in Gelendzhik maintains the research (observational) site for year round multi-disciplinary studies and monitoring of the marine environment in the coastal zone. Analysis of the data obtained at the observational site revealed the existence of well pronounced short-term variability of coastal zone hydrodynamics at time scales from 1-3 days to 1-2 weeks. The paper examines the role of external forcing (including the impact of adjoined open sea dynamics and wind stress) in the short-term variability of hydrodynamics and upper mixed layer evolution.

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SHORT-TERM VARIABILITY OF COASTAL ZONE HYDRODYNAMICS UNDER AN EXTERNAL FORCING: OBSERVATIONS AT THE BLACK SEA RESEARCH SITE OF SIO RAS

Proceedings of International Conference "Managinag risks to coastal regions and communities in a changinag world" (EMECS'11 - SeaCoasts XXVI) ◽

10.31519/conferencearticle_5b1b93915d1c11.31020337 ◽

2017 ◽

Author(s):

Andrey Zatsepin ◽

Sergey Kuklev ◽

Alexander Ostrovskii ◽

...

Keyword(s):

Coastal Zone ◽

The Black Sea ◽

External Forcing ◽

Short Term ◽

Shirshov Institute ◽

Open Sea ◽

Observational Site ◽

Upper Mixed Layer ◽

The Impact ◽

Short Term Variability

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The impact of short-term variability and uncertainty on long-term power planning

Annals of Operations Research ◽

10.1007/s10479-018-3097-3 ◽

2018 ◽

Vol 284 (1) ◽

pp. 199-223 ◽

Cited By ~ 4

Author(s):

Henrik C. Bylling ◽

Salvador Pineda ◽

Trine K. Boomsma

Keyword(s):

Short Term ◽

The Impact ◽

Short Term Variability

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Short-term variability of intertidal microphytobenthic production using an oxygen microprofiling system

Marine and Freshwater Research ◽

10.1071/mf08070 ◽

2009 ◽

Vol 60 (7) ◽

pp. 712 ◽

Cited By ~ 14

Author(s):

Lionel Denis ◽

Pierre-Emmanuel Desreumaux

Keyword(s):

Primary Production ◽

Incident Light ◽

High Tide ◽

Short Term ◽

Overlying Water ◽

Benthic Primary Production ◽

Production Values ◽

The Impact ◽

Oxygen Microprofiles ◽

Short Term Variability

Despite their high productivity and their key role in coastal processes, intertidal areas remain poorly documented because alternating conditions of sediment-water and sediment-air interfaces result in inaccurate temporal estimations of interfacial carbon exchanges. This study describes the short-term variability of microphytobenthic production in an estuarine mudflat (the Canche estuary of the English Channel) by using an autonomous acquisition system for oxygen microprofiles. More than 240 profiles were measured at low and high tide during three deployments performed within a 3-week period (April–May 2007). Additional measurements characterised the surficial sediments (granulometry, porosity, chlorophyll a, temperature, salinity) and incident light. Depth-integrated gross production values were correlated with light intensity and reached up to 146 mg C m–2 h–1, while the turbidity of the overlying water prevented any primary production during immersion. Photosynthesis–irradiance curves were highly variable between field campaigns. Indeed, we have recorded a drastic reduction in microphytobenthic production, which might result from a pulse input of polychaete juveniles (Lanice conchilega). Ephemeral structures, such as invertebrate tubes, are seldom considered as factors that may influence the variability of benthic primary production. Monitoring oxygen microprofiles may be a useful tool for understanding and quantifying the impact of short-term temporal changes on the budgets of microphytobenthic production.

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Quantifying the impact of emission outbursts and non-stationary flow on eddy covariance CH<sub>4</sub> flux measurements using wavelet techniques

10.5194/bg-2019-92 ◽

2019 ◽

Author(s):

Mathias Göckede ◽

Fanny Kittler ◽

Carsten Schaller

Keyword(s):

Eddy Covariance ◽

Methane Flux ◽

Stationary Flow ◽

Methane Emissions ◽

Short Term ◽

Flux Measurements ◽

Systematic Biases ◽

Wavelet Techniques ◽

The Impact ◽

Short Term Variability

Abstract. Methane flux measurements by the eddy-covariance technique are subject to large uncertainties, particularly linked to the partly highly intermittent nature of methane emissions. Outbursts of high methane emissions, termed event fluxes, hold the potential to introduce systematic biases into derived methane budgets, since under such conditions the assumption of stationarity of the flow is violated. In this study, we investigate the net impact of this effect by comparing eddy-covariance fluxes against a wavelet-derived reference that is not negatively influenced by non-stationarity. Our results demonstrate that methane emission events influenced 3–4 % of the flux measurements, and did not lead to systematic biases in methane budgets for the analyzed summer season; however, the presence of events substantially increased uncertainties in short-term flux rates. The wavelet results provided an excellent reference to evaluate the performance of three different gapfilling approaches for eddy-covariance methane fluxes, and we show that none of them could reproduce the range of observed flux rates. The integrated performance of the gapfilling methods for the longer-term dataset varied between the two eddy-covariance towers involved in this study, and we show that gapfilling remains a large source of uncertainty linked to limited insights into the mechanisms governing the short-term variability in methane emissions. With the capability to broaden our observational methane flux database to a wider range of conditions, including the direct resolution of short term variability at the order of minutes, wavelet-derived fluxes hold the potential to generate new insight into methane exchange processes with the atmosphere, and therefore also improve our understanding of the underlying processes.

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Impacts of Climate Change: Can Fisheries and Aquaculture Sectors Survive the Wave?

International Journal of Global Sustainability ◽

10.5296/ijgs.v4i1.17245 ◽

2020 ◽

Vol 4 (1) ◽

pp. 78

Author(s):

Talent Ndlovu ◽

Sylvain Charlebois

Keyword(s):

Climate Change ◽

Global Warming ◽

Food Security ◽

Food Insecurity ◽

Holistic Approach ◽

Short Term ◽

Ocean Ecosystem ◽

The Impact ◽

Impacts Of Climate Change

Studies have shown the impact of climate change on the ocean ecosystem and the fishing and aquaculture sectors. As global warming intensifies, this will impact communities and communities as the populations of some fish species decline or increase. Research on the impacts of climate change to fisheries will facilitate the development of policies, helping communities to adapt while ensuring resilience and sustainability of the sector(s). This paper assesses the short term and long-term impacts of climate change to the ocean ecosystem, the consequences to economies and communities that rely on fishing for food security. It begins with a review of peer reviewed literature, followed by an analysis of the current policies and ends with some recommendations for governments in the sustainability and management of the ecosystem in the future. Important to note is the impact of human generated hazards and how a more holistic approach to minimizing risks to the ocean ecosystem could resolve threats of food insecurity in future.

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