Zooplankton Biomass in the Southern Gulf of St. Lawrence: Spatial Patterns and the Influence of Freshwater Runoff

1994 ◽  
Vol 51 (3) ◽  
pp. 617-635 ◽  
Author(s):  
Yves De Lafontaine
Keyword(s):  
Large Scale ◽  
Salinity Gradient ◽  
Distribution Patterns ◽  
Zooplankton Biomass ◽  
Freshwater Input ◽  
Entire Area ◽  
Freshwater Runoff ◽  
Coastal Shelf ◽  
Runoff Variability

The role of advection of freshwater input in Zooplankton distribution was evaluated from 16 surveys carried out in the southern Gulf of St. Lawrence during 1967–71. Biomass was structured according to two main patterns: large-scale gradients (> 150 km) over the entire area and mesoscafe (≈25 km) patches. Patterns exhibited seasonal and interannual variability without any sign of recurrence through time, unlike the spatial structure of surface water temperature and salinity which was typical of large-scale dispersion gradients resulting from the seasonal input of freshwater into the area. In most cases, overall distribution patterns of biomass and hydrographic variables were not significantly correlated, indicating that biomass patterns in the southern Gulf were not related to water mass characteristics and advection of freshwater runoff over the entire area. Although mesoscale patchiness was unrelated to hydrographic processes, patch size (≈25 km) was similar to estimates obtained for the northern Gulf and for other coastal shelf areas. Large-scale gradients in biomass may correspond to species changes in relation to the salinity gradient and/or topography and bathymetric features. I conclude that biomass alone is not an adequate predictor for monitoring changes and variability of Zooplankton in response to runoff variability.

scholarly journals Environmental Drivers of Diversification and Hybridization in Neotropical Butterflies

2021 ◽  
Vol 9 ◽  
Author(s):  
Nicol Rueda-M ◽  
Fabian C. Salgado-Roa ◽  
Carlos H. Gantiva-Q ◽  
Carolina Pardo-Díaz ◽  
Camilo Salazar
Keyword(s):  
Phylogenetic Diversity ◽  
Large Scale ◽  
Distribution Patterns ◽  
Environmental Drivers ◽  
General Distribution ◽  
Ecological Interactions ◽  
Future Studies ◽  
Topographic Complexity ◽  
Geographic Patterns

Studying how the environment shapes current biodiversity patterns in species rich regions is a fundamental issue in biogeography, ecology, and conservation. However, in the Neotropics, the study of the forces driving species distribution and richness, is mostly based on vertebrates and plants. In this study, we used 54,392 georeferenced records for 46 species and 1,012 georeferenced records for 38 interspecific hybrids of the Neotropical Heliconius butterflies to investigate the role of the environment in shaping their distribution and richness, as well as their geographic patterns of phylogenetic diversity and phylogenetic endemism. We also evaluated whether niche similarity promotes hybridization in Heliconius. We found that these insects display five general distribution patterns mostly explained by precipitation and isothermality, and to a lesser extent, by altitude. Interestingly, altitude plays a major role as a predictor of species richness and phylogenetic diversity, while precipitation explains patterns of phylogenetic endemism. We did not find evidence supporting the role of the environment in facilitating hybridization because hybridizing species do not necessarily share the same climatic niche despite some of them having largely overlapping geographic distributions. Overall, we confirmed that, as in other organisms, high annual temperature, a constant supply of water, and spatio-topographic complexity are the main predictors of diversity in Heliconius. However, future studies at large scale need to investigate the effect of microclimate variables and ecological interactions.

Possible effect of Balanus improvisus on Cerastoderma glaucum distribution in the south-western Caspian Sea

2015 ◽  
Vol 96 (5) ◽  
pp. 1031-1040 ◽  
Author(s):  
Alireza Mirzajani ◽  
Amir Hossein Hamidian ◽  
Siamak Bagheri ◽  
Mahmoud Karami
Keyword(s):  
Caspian Sea ◽  
Salinity Gradient ◽  
Nutrient Content ◽  
Distribution Patterns ◽  
The South ◽  
Negative Effects ◽  
Cerastoderma Glaucum ◽  
Balanus Improvisus ◽  
Linear Growth Model

We studied the communities of the invasive Balanus improvisus and native Cerastoderma glaucum populations in the south-western Caspian Sea. The massive movement of live Bivalvia attached to Cirripedia colonies along the studied coastline strengthens the hypotheses asserting the possible negative effects of exotic species on endemic species. Different live stages of both animals including meroplankton and macro-invertebrates were considered in the analysis. Bivalvia larvae showed a downward trend in population, in contrast with an upward trend of Cirripedia larvae from 1996 to 2013. The abundance of C. glaucum decreased west to east along the sea shore in contrast with increasing biomass of B. improvisus. Both Bivalvia and Cirripedia larvae did not show any overlapping temporal abundance. The Cirripedia larvae showed its highest abundance in winter while the bloom of Bivalvia larvae occurred in April and May during 2004–2013. The biomass of B. improvisus reported in this study was higher than those reported for the northern parts and for the middle parts. Distribution patterns of both species were described based on temperature, salinity gradient and local nutrient content. A non-linear growth model of Bivalvia showed the short-term effects of Cirripedia on Bivalvia growth. The controversy between the effects of Cirripedia on the movement of two different Cardiidae (C. glaucum, which is affected by the presence of B. improvisus, and Adacna vitrea with no attached Cirripedia) highlights the contributing role of several other factors including ecosystem degradation.

The Role of Sense of Direction and Other Factors During Navigation in a Large-Scale, Unconstrained Environment

2013 ◽  
Author(s):  
Elisabeth J. Ploran ◽  
Ericka Rovira ◽  
James C. Thompson ◽  
Raja Parasuraman
Keyword(s):  
Large Scale ◽  
Sense Of Direction

Magnetic Properties of xCeO2•(50 − x) PbO•50B2O3 Glasses and Glass Ceramics

2017 ◽  
Vol 13 (1) ◽  
pp. 4486-4494 ◽  
Author(s):  
G.El Damrawi ◽  
F. Gharghar
Keyword(s):  
Magnetic Properties ◽  
Large Scale ◽  
Glass Ceramics ◽  
Magnetic Behavior ◽  
Crystal Formation ◽  
Dual Roles ◽  
Effective Agent ◽  
Ordered Structures ◽  
Essential Change

Cerium oxide in borate glasses of composition xCeO2·(50 − x)PbO·50B2O3 plays an important role in changing both microstructure and magnetic behaviors of the system. The structural role of CeO2 as an effective agent for cluster and crystal formation in borate network is clearly evidenced by XRD technique. Both structure and size of well-formed cerium separated clusters have an effective influence on the structural properties. The cluster aggregations are documented to be found in different range ordered structures, intermediate and long range orders are the most structures in which cerium phases are involved. The nano-sized crystallized cerium species in lead borate phase are evidenced to have magnetic behavior.  The criteria of building new specific borate phase enriched with cerium as ferrimagnetism has been found to keep the magnetization in large scale even at extremely high temperature. Treating the glass thermally or exposing it to an effective dose of ionized radiation is evidenced to have an essential change in magnetic properties. Thermal heat treatment for some of investigated materials is observed to play dual roles in the glass matrix. It can not only enhance alignment processes of the magnetic moment but also increases the capacity of the crystallite species in the magnetic phases. On the other hand, reverse processes are remarked under the effect of irradiation. The magnetization was found to be lowered, since several types of the trap centers which are regarded as defective states can be produced by effect of ionized radiation. 

The Impact of Quantitative Easing on Emerging Markets – Literature Review

e-Finanse ◽  
2018 ◽  
Vol 14 (4) ◽  
pp. 67-76
Author(s):  
Piotr Bartkiewicz
Keyword(s):  
Emerging Markets ◽  
Large Scale ◽  
Empirical Literature ◽  
Quantitative Easing ◽  
Methodological Choices ◽  
The Subject ◽  
Methodological Approaches ◽  
The Impact ◽  
Sufficient Precision

AbstractThe article presents the results of the review of the empirical literature regarding the impact of quantitative easing (QE) on emerging markets (EMs). The subject is of interest to policymakers and researchers due to the increasingly larger role of EMs in the world economy and the large-scale capital flows occurring after 2009. The review is conducted in a systematic manner and takes into consideration different methodological choices, samples and measurement issues. The paper puts the summarized results in the context of transmission channels identified in the literature. There are few distinct methodological approaches present in the literature. While there is a consensus regarding the direction of the impact of QE on EMs, its size and durability have not yet been assessed with sufficient precision. In addition, there are clear gaps in the empirical findings, not least related to relative underrepresentation of the CEE region (in particular, Poland).

Age Advantages of Emotional Experience during the COVID-19 Pandemic are Robust, but Diminished Compared to Pre-pandemic Conditions

2020 ◽  
Author(s):  
Rui Sun ◽  
Disa Sauter
Keyword(s):  
Older Adults ◽  
Large Scale ◽  
Negative Emotion ◽  
Emotional Experience ◽  
Negative Emotions ◽  
Older Individuals ◽  
Selection Strategies ◽  
Scale Test ◽  
Prolonged Stress

Getting old is generally seen as unappealing, yet aging confers considerable advantages in several psychological domains (North & Fiske, 2015). In particular, older adults are better off emotionally than younger adults, with aging associated with the so-called “age advantages,” that is, more positive and less negative emotional experiences (Carstensen et al., 2011). Although the age advantages are well established, it is less clear whether they occur under conditions of prolonged stress. In a recent study, Carstensen et al (2020) demonstrated that the age advantages persist during the COVID-19 pandemic, suggesting that older adults are able to utilise cognitive and behavioural strategies to ameliorate even sustained stress. Here, we build on Carstensen and colleagues’ work with two studies. In Study 1, we provide a large-scale test of the robustness of Carstensen and colleagues’ finding that older individuals experience more positive and less negative emotions during the COVID-19 pandemic. We measured positive and negative emotions along with age information in 23,629 participants in 63 countries in April-May 2020. In Study 2, we provide a comparison of the age advantages using representative samples collected before and during the COVID-19 pandemic. We demonstrate that older people experience less negative emotion than younger people during the prolonged stress of the COVID-19 pandemic. However, the advantage of older adults was diminished during the pandemic, pointing to a likely role of older adults use of situation selection strategies (Charles, 2010).

Legislative tools in the Czech watershed management policy

1996 ◽  
Vol 33 (4-5) ◽  
pp. 39-44
Author(s):  
J. Holas ◽  
M. Konvicková
Keyword(s):  
Watershed Management ◽  
Large Scale ◽  
Agricultural Practices ◽  
Farming System ◽  
Management Policy ◽  
Running Water ◽  
The Czech Republic ◽  
Law System ◽  
Water Quality Regulations

Potential environmental impacts as a result of large-scale farming system in the Czech Republic have created a great deal of concern in recent years. This concern has led to several studies to identify the role of new regulations, directives and other legislative issues in the field of water pollution control. The set of legislative tools related to watershed management policy to promote better agricultural practices is shortly reviewed. The paper emphasises the running water law system amendment with respect to European community water quality regulations.

Inflammatory Biomarkers in Atrial Fibrillation

2019 ◽  
Vol 26 (5) ◽  
pp. 837-854 ◽  
Author(s):  
Effimia Zacharia ◽  
Nikolaos Papageorgiou ◽  
Adam Ioannou ◽  
Gerasimos Siasos ◽  
Spyridon Papaioannou ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Plasma Levels ◽  
Large Scale ◽  
Inflammatory Biomarkers ◽  
Inflammatory Pathways ◽  
Inflammatory State ◽  
Anti Inflammatory ◽  
Underlying Mechanisms

During the last few years, a significant number of studies have attempted to clarify the underlying mechanisms that lead to the presentation of atrial fibrillation (AF). Inflammation is a key component of the pathophysiological processes that lead to the development of AF; the amplification of inflammatory pathways triggers AF, and, in tandem, AF increases the inflammatory state. Indeed, the plasma levels of several inflammatory biomarkers are elevated in patients with AF. In addition, the levels of specific inflammatory biomarkers may provide information regarding to the AF duration. Several small studies have assessed the role of anti-inflammatory treatment in atrial fibrillation but the results have been contradictory. Large-scale studies are needed to evaluate the role of inflammation in AF and whether anti-inflammatory medications should be routinely administered to patients with AF.

Situational Breakdowns

2019 ◽  
Author(s):  
Anne Nassauer
Keyword(s):  
United States ◽  
Large Scale ◽  
Contextual Factors ◽  
The United States ◽  
Social Outcomes ◽  
Dynamic Processes ◽  
Collective Decisions ◽  
Different Types ◽  
The Impact

This book provides an account of how and why routine interactions break down and how such situational breakdowns lead to protest violence and other types of surprising social outcomes. It takes a close-up look at the dynamic processes of how situations unfold and compares their role to that of motivations, strategies, and other contextual factors. The book discusses factors that can draw us into violent situations and describes how and why we make uncommon individual and collective decisions. Covering different types of surprise outcomes from protest marches and uprisings turning violent to robbers failing to rob a store at gunpoint, it shows how unfolding situations can override our motivations and strategies and how emotions and culture, as well as rational thinking, still play a part in these events. The first chapters study protest violence in Germany and the United States from 1960 until 2010, taking a detailed look at what happens between the start of a protest and the eruption of violence or its peaceful conclusion. They compare the impact of such dynamics to the role of police strategies and culture, protesters’ claims and violent motivations, the black bloc and agents provocateurs. The analysis shows how violence is triggered, what determines its intensity, and which measures can avoid its outbreak. The book explores whether we find similar situational patterns leading to surprising outcomes in other types of small- and large-scale events: uprisings turning violent, such as Ferguson in 2014 and Baltimore in 2015, and failed armed store robberies.

Approaches to Supporting Local and Community Development

2018 ◽  
Author(s):  
Liesel Mack Filgueiras ◽  
Andreia Rabetim ◽  
Isabel Aché Pillar
Keyword(s):  
Large Scale ◽  
Mining Company ◽  
The Sustainable Development ◽  
Social Partnership ◽  
The Public ◽  
Mining Investment ◽  
The Social ◽  
Corporate Social

Reflection about the role of community engagement and corporate social investment in Brazil, associated with the presence of a large economic enterprise, is the major stimulus of this chapter. It seeks to present how cross-sector governance can contribute to the social development of a city and how this process can be led by a partnership comprising a corporate foundation, government, and civil society. The concept of the public–private social partnership (PPSP) is explored: a strategy for building a series of inter-sectoral alliances aimed at promoting the sustainable development of territories where the company has large-scale enterprises, through joint efforts towards integrated long-term strategic planning, around a common agenda. To this end, the case of Canaã dos Carajás is introduced, a municipality in the State of Pará, in the Amazon region, where large-scale mining investment is being carried out by the mining company Vale SA.

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