scholarly journals Multivariate benthic ecosystem functioning in the Arctic – benthic fluxes explained by environmental parameters in the southeastern Beaufort Sea

2012 ◽  
Vol 9 (11) ◽  
pp. 16933-16976 ◽  
Author(s):  
H. Link ◽  
G. Chaillou ◽  
A. Forest ◽  
D. Piepenburg ◽  
P. Archambault
Keyword(s):  
Spatial Variation ◽  
Bottom Water ◽  
Environmental Variability ◽  
Environmental Parameters ◽  
The Arctic ◽  
Benthic Fluxes ◽  
Short Term ◽  
Water Oxygen ◽  
The Impact

Abstract. The effects of climate change on Arctic marine ecosystems and their biogeochemical cycles are difficult to predict given the complex physical, biological and chemical interactions among the ecosystem components. To predict the impact of future changes on benthic biogeochemical fluxes in the Arctic, it is important to understand the influence of short-term (seasonal to annual), long-term (annual to decadal) and other environmental variability on their spatial distribution. In summer 2009, we measured fluxes of dissolved oxygen, nitrate, nitrite, ammonia, soluble reactive phosphate and silicic acid at the sediment-water interface at eight sites in the southeastern Beaufort Sea at water depths from 45 to 580 m to address the following question and hypotheses using a statistical approach: (1) What is the spatial variation of benthic boundary fluxes (sink and source)? (2) The classical proxy of benthic activity, oxygen flux, does not determine overall spatial variation in fluxes. (3) A different combination of environmental conditions that vary either on a long-term (decadal) or short-term (seasonal to annual) scale determine each single flux. And (4) A combination of environmental conditions varying on the short and long-term scale drive the overall spatial variation in benthic boundary fluxes. The spatial pattern of the measured benthic boundary fluxes was heterogeneous. Multivariate analysis of flux data showed that no single or reduced combination of fluxes could explain the majority of spatial variation. We tested the influence of eight environmental parameters: sinking flux of particulate organic carbon above the bottom, sediment surface Chl a (both short-term), porosity, surface manganese and iron concentration, bottom water oxygen concentrations (all long-term), phaeopigments (intermediate-term influence) and Δ13Corg (terrestrial influence) on benthic fluxes. Short-term environmental parameters were most important for explaining oxygen, ammonium and nitrate fluxes. Long-term parameters together with Δ13Corg signature explained most of the spatial variation in phosphate, nitrate and nitrite fluxes. Sediment pigments and Δ13Corg levels in surficial sediments were most important to explain fluxes of silicic acid. The overall spatial distribution of fluxes could be best explained (57%) by the combination of sediment Chla, phaeopigments, Δ13Corg, surficial manganese and bottom water oxygen concentration. We conclude that it is necessary to consider long-term environmental variability in the prediction of the impact of ongoing short-term environmental changes on the flux of oxygen and nutrients in Arctic sediments. Our results contribute to improve ecological models predicting the impact if climate change on the functioning of marine ecosystems.

scholarly journals Multivariate benthic ecosystem functioning in the Arctic – benthic fluxes explained by environmental parameters in the southeastern Beaufort Sea

2013 ◽  
Vol 10 (9) ◽  
pp. 5911-5929 ◽  
Author(s):  
H. Link ◽  
G. Chaillou ◽  
A. Forest ◽  
D. Piepenburg ◽  
P. Archambault
Keyword(s):  
Environmental Variability ◽  
Environmental Parameters ◽  
The Arctic ◽  
Sediment Surface ◽  
Benthic Fluxes ◽  
Short Term ◽  
Chl A ◽  
Water Oxygen ◽  
The Impact

Abstract. The effects of climate change on Arctic marine ecosystems and their biogeochemical cycles are difficult to predict given the complex physical, biological and chemical interactions among the ecosystem components. We studied benthic biogeochemical fluxes in the Arctic and the influence of short-term (seasonal to annual), long-term (annual to decadal) and other environmental variability on their spatial distribution to provide a baseline for estimates of the impact of future changes. In summer 2009, we measured fluxes of dissolved oxygen, nitrate, nitrite, ammonia, soluble reactive phosphate and silicic acid at the sediment–water interface at eight sites in the southeastern Beaufort Sea at water depths from 45 to 580 m. The spatial pattern of the measured benthic boundary fluxes was heterogeneous. Multivariate analysis of flux data showed that no single or reduced combination of fluxes could explain the majority of spatial variation, indicating that oxygen flux is not representative of other nutrient sink–source dynamics. We tested the influence of eight environmental parameters on single benthic fluxes. Short-term environmental parameters (sinking flux of particulate organic carbon above the bottom, sediment surface Chl a) were most important for explaining oxygen, ammonium and nitrate fluxes. Long-term parameters (porosity, surface manganese and iron concentration, bottom water oxygen concentrations) together with δ13Corg signature explained most of the spatial variation in phosphate, nitrate and nitrite fluxes. Variation in pigments at the sediment surface was most important to explain variation in fluxes of silicic acid. In a model including all fluxes synchronously, the overall spatial distribution could be best explained (57%) by the combination of sediment Chl a, phaeopigments, δ13Corg, surficial manganese and bottom water oxygen concentration. We conclude that it is necessary to consider long-term environmental variability along with rapidly ongoing environmental changes to predict the flux of oxygen and nutrients across Arctic sediments even at short timescales. Our results contribute to improve ecological models predicting the impact of climate change on the functioning of marine ecosystems.

Impact of the 2014 Major Baltic Inflow on benthic fluxes of ferrous iron and phosphate below the permanent halocline in the southern Baltic Sea

2018 ◽  
Vol 47 (3) ◽  
pp. 275-287
Author(s):  
Olga Brocławik ◽  
Katarzyna Łukawska-Matuszewska ◽  
Jerzy Bolałek
Keyword(s):  
Pore Water ◽  
Ferrous Iron ◽  
Bottom Water ◽  
Reductive Dissolution ◽  
Benthic Fluxes ◽  
Dissolved Iron ◽  
Water Oxygen ◽  
One Year ◽  
Total Dissolved Iron ◽  
The Impact

Abstract The impact of 2014 Major Baltic Inflow (MBI) on ferrous iron (FFe(II)) and phosphate (FPO43–) benthic fluxes was investigated. Sampling took place few months after the MBI, in August 2015, and over one year after the inflow, in February 2016. Materials were collected from three sites (depth of 106–108 m) located in the Gdańsk Deep. Total dissolved iron, Fe(II), phosphate, H2S and sulfate were analyzed in bottom and pore water. Benthic fluxes were estimated using Fick’s first law. All fluxes were directed from sediment. FFe(II) ranged from 0.31 × 10–2 to 1.25 × 10–2 μmol m–2 hr–1 and FPO43– from 1.53 to 2.70 μmol m–2 hr–1. At the deepest site, FPO43– was similar in both seasons, while at two other sites fluxes in August 2015 were 40–50% smaller than in February 2016. The increase in bottom water oxygen after the MBI enhanced Fe(oxyhydr)oxides formation. As a consequence, bottom and pore water concentrations of Fe(II) and FFe(II), decreased. Adsorption of phosphate onto Fe(oxyhydr)oxides resulted in binding of P in surface sediment and lower FPO43– in August 2015. This was particularly evident at the shallowest site. The reductive dissolution of Fe(oxyhydr)oxides and desorption of P during the subsequent months resulted in higher FPO43– in February 2016.

SUMBER-SUMBER RESILIENSI PADA REMAJA AKHIR YANG MENGALAMI KEKERASAN DARI ORANGTUA PADA MASA KANAK-KANAK

Psibernetika ◽  
2018 ◽  
Vol 11 (1) ◽  
Author(s):  
Devina Calista ◽  
Garvin Garvin
Keyword(s):  
Late Adolescents ◽  
Long Term Effects ◽  
Short Term ◽  
Parental Affection ◽  
Resilience Factors ◽  
Childhood Violence ◽  
Past Experiences ◽  
The Impact ◽  
Depth Interviews

<p><em>Child abuse by parents is common in households. The impact of violence on children will bring short-term effects and long-term effects that can be attributed to their various emotional, behavioral and social problems in the future; especially in late adolescence that will enter adulthood. Resilience factors increase the likelihood that adolescents who are victims of childhood violence recover from their past experiences</em><em>,</em><em> become more powerful individuals and have a better life. The purpose of this study was to determine the source of resilience in late adolescents who experienced violence from parents in their childhood. This research uses qualitative research methods with in-depth interviews as a method of data collection. The result shows that the three research participants have the aspects of "I Have", "I Am", and "I Can"; a participant has "I Can" aspects as a source of resilience, and one other subject has no source of resilience. The study concluded that parental affection and acceptance of the past experience have role to the three sources of resilience (I Have, I Am, and I Can)</em></p><p><em> </em></p><p><strong><em>Keyword : </em></strong><em>Resilience, adolescence, violence, parents</em></p>

Forecasting Revenue Impacts from COVID-19: The Case of Florida Municipalities

2021 ◽  
pp. 0160323X2110120
Author(s):  
Hai (David) Guo ◽  
Can Chen
Keyword(s):  
Local Government ◽  
Short Term ◽  
Fiscal Planning ◽  
Revenue Structure ◽  
Municipal Managers ◽  
The Impact

Early in the pandemic, Florida municipal managers indicated that forecasting the impact on local revenues was one of their top priorities in responding to the pandemic, yet such a tool has not been widely available. This study offers simple and straightforward fiscal planning guides for assessing the short-term and long-term impacts of the COVID 19 recession on local government revenues by estimating the revenue declines among 411 Florida municipalities from FY 2021 to FY 2023. The forecast results predict revenues will be reduced by $5.11 billion from 2019 pre-pandemic levels for Florida cities in fiscal years 2021 through 2023. The decline is forecast to be 3.54 percent in FY 2021, 4.02 percent in FY 2022, and 3.29 percent in FY 2023. The revenue structure matters for estimating the revenue decline.

scholarly journals Paleolithic Diet—Effect on the Health Status and Performance of Athletes?

Nutrients ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 1019
Author(s):  
Barbara Frączek ◽  
Aleksandra Pięta ◽  
Adrian Burda ◽  
Paulina Mazur-Kurach ◽  
Florentyna Tyrała
Keyword(s):  
Blood Pressure ◽  
Body Mass ◽  
Positive Impact ◽  
Model Assessment ◽  
Paleolithic Diet ◽  
Short Term ◽  
Positive Effects ◽  
Short And Long Term ◽  
The Impact

The aim of this meta-analysis was to review the impact of a Paleolithic diet (PD) on selected health indicators (body composition, lipid profile, blood pressure, and carbohydrate metabolism) in the short and long term of nutrition intervention in healthy and unhealthy adults. A systematic review of randomized controlled trials of 21 full-text original human studies was conducted. Both the PD and a variety of healthy diets (control diets (CDs)) caused reduction in anthropometric parameters, both in the short and long term. For many indicators, such as weight (body mass (BM)), body mass index (BMI), and waist circumference (WC), impact was stronger and especially found in the short term. All diets caused a decrease in total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG), albeit the impact of PD was stronger. Among long-term studies, only PD cased a decline in TC and LDL-C. Impact on blood pressure was observed mainly in the short term. PD caused a decrease in fasting plasma (fP) glucose, fP insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) and glycated hemoglobin (HbA1c) in the short run, contrary to CD. In the long term, only PD caused a decrease in fP glucose and fP insulin. Lower positive impact of PD on performance was observed in the group without exercise. Positive effects of the PD on health and the lack of experiments among professional athletes require longer-term interventions to determine the effect of the Paleo diet on athletic performance.

Methods to Reduce Traffic Speed in High-Pedestrian Rural Areas

2003 ◽  
Vol 1828 (1) ◽  
pp. 31-37 ◽  
Author(s):  
Ali Kamyab ◽  
Steve Andrle ◽  
Dennis Kroeger ◽  
David S. Heyer
Keyword(s):  
Rural Areas ◽  
Speed Limit ◽  
Single Word ◽  
Short Term ◽  
Speed Reduction ◽  
Traffic Calming ◽  
Reduction Strategies ◽  
Long Term Impact ◽  
The Impact

Many Minnesota counties are faced with the problem of high vehicle speeds through towns or resort areas that have significant pedestrian traffic. The impact of speed reduction strategies in high-pedestrian areas in rural counties of Minnesota was investigated. Speed data were collected at two selected study sites under their existing conditions ("no-treatment" or "before" condition) and after the proposed speed reduction strategies were installed. Second "after" data conditions were collected to study the short-term and long-term impact of the implemented strategies. The traffic-calming techniques employed at the Twin Lakes site consisted of removable pedestrian islands and pedestrian crossing signs. A dynamic variable message sign that sent a single-word message ("Slow") to motorists traveling over the speed limit was installed at the Bemidji site. The research study shows that the traffic-calming strategy deployed in Twin Lakes was effective in significantly reducing the mean speed and improving speed limit compliance in both the short term and long term. Despite proven effectiveness, the deployed speed reduction treatment in Bemidji Lake failed to lower the speed at the study site. The single-word message on the sign and the location of the sign, as well as a lack of initial enforcement, were the primary reasons for such failure.

The implications of selected processing methods on satellite altimetry derived sea ice thickness state and trends in the seasonal ice zone

2021 ◽  
Author(s):  
Isolde Glissenaar ◽  
Jack Landy ◽  
Alek Petty ◽  
Nathan Kurtz ◽  
Julienne Stroeve
Keyword(s):  
Sea Ice ◽  
Snow Depth ◽  
Satellite Altimetry ◽  
Region Of Interest ◽  
The Arctic ◽  
Ice Thickness ◽  
Sea Ice Thickness ◽  
Baffin Bay ◽  
The Impact

&lt;p&gt;The ice cover of the Arctic Ocean is increasingly becoming dominated by seasonal sea ice. It is important to focus on the processing of altimetry ice thickness data in thinner seasonal ice regions to understand seasonal sea ice behaviour better. This study focusses on Baffin Bay as a region of interest to study seasonal ice behaviour.&lt;/p&gt;&lt;p&gt;We aim to reconcile the spring sea ice thickness derived from multiple satellite altimetry sensors and sea ice charts in Baffin Bay and produce a robust long-term record (2003-2020) for analysing trends in sea ice thickness. We investigate the impact of choosing different snow depth products (the Warren climatology, a passive microwave snow depth product and modelled snow depth from reanalysis data) and snow redistribution methods (a sigmoidal function and an empirical piecewise function) to retrieve sea ice thickness from satellite altimetry sea ice freeboard data.&lt;/p&gt;&lt;p&gt;The choice of snow depth product and redistribution method results in an uncertainty envelope around the March mean sea ice thickness in Baffin Bay of 10%. Moreover, the sea ice thickness trend ranges from -15 cm/dec to 20 cm/dec depending on the applied snow depth product and redistribution method. Previous studies have shown a possible long-term asymmetrical trend in sea ice thinning in Baffin Bay. The present study shows that whether a significant long-term asymmetrical trend was found depends on the choice of snow depth product and redistribution method. The satellite altimetry sea ice thickness results with different snow depth products and snow redistribution methods show that different processing techniques can lead to different results and can influence conclusions on total and spatial sea ice thickness trends. Further processing work on the historic radar altimetry record is needed to create reliable sea ice thickness products in the marginal ice zone.&lt;/p&gt;

Impacts of the COVID-19 pandemic on protected area management and conservation outcomes in Mexico

2021 ◽  
Author(s):  
Kathryn Powlen ◽  
Kelly W. Jones ◽  
Elva Ivonne Bustamante Moreno ◽  
Maira Abigail Ortíz Cordero ◽  
Jennifer N. Solomon ◽  
...  
Keyword(s):  
Management Support ◽  
Short Term ◽  
Group Data ◽  
Management Capacity ◽  
Focus Group Data ◽  
Technical Capacity ◽  
The Impact ◽  
Relief Efforts ◽  
Management And Conservation

Protected areas (PAs) are under immense pressure to safeguard much of the world’s remaining biodiversity and can be strained by unpredicted events such as the COVID-19 pandemic. Understanding the extent of the pandemic on PA inputs, mechanisms, and conservation outcomes is critical for recovery and future planning to buffer against these types of events. We use survey and focus group data to quantify the impact of the pandemic on Mexico’s PA network and outline the pathways that led to conservation outcomes. On average, across 62 PAs, we find substantial changes in management capacity, monitoring, and tourism, and a slight increase in non-compliant activities. Our findings highlight the need to increase short-term relief efforts and long-term livelihood diversification initiatives for communities dependent on tourism, who were most vulnerable during the pandemic. Increased management support, including technical capacity and financial resources, could also better sustain management activities in future shocks.

Does salience matter in investment decision?

Kybernetes ◽  
2019 ◽  
Vol 48 (8) ◽  
pp. 1894-1912
Author(s):  
Samra Chaudary
Keyword(s):  
Investment Decision ◽  
Investment Decisions ◽  
Equation Modeling ◽  
Individual Investors ◽  
Short Term ◽  
Content Type ◽  
Multigroup Analysis ◽  
Money Managers ◽  
The Impact

Purpose The paper takes a behavioral approach by making use of the prospect theory to unveil the impact of salience on short-term and long-term investment decisions. This paper aims to investigate the group differences for two types of investors’ groups, i.e. individual investors and professional investors. Design/methodology/approach The study uses partial least square-based structural equation modeling technique, measurement invariance test and multigroup analysis test on a unique data set of 277 active equity traders which included professional money managers and individual investors. Findings Results showed that salience has a significant positive impact on both short-term and long-term investment decisions. The impact was almost 1.5 times higher for long-term investment decision as compared to short-term decision. Furthermore, multigroup analysis revealed that the two groups (individual investors and professional investors) were statistically significantly different from each other. Research limitations/implications The study has implications for financial regulators, money managers and individual investors as it was found that individual investors suffer more with salience heuristic and may end up with sub-optimal portfolios due to inefficient diversification. Thus, investors should be cautious in fully relying on salience and avoid such bias to improve investment returns. Practical implications The study concludes with a discussion of policy and regulatory implications on how to minimize salience bias to achieve optimum and diversified portfolios. Originality/value The study has significantly contributed to the growing body of applied behavioral research in the discipline of finance.

Sign in / Sign up

Export Citation Format

Share Document