scholarly journals Low Genetic Connectivity of Strongly Inbred Ruppia brevipedunculata in Aquaculture Dominated Lagoons (Viet Nam)

2021 ◽  
Vol 2 ◽  
Author(s):  
Ludwig Triest ◽  
Jasper Dierick ◽  
Thi Thuy Hang Phan ◽  
Quang Doc Luong ◽  
Nguyen Quang Huy ◽  
...  
Keyword(s):  
Water Surface ◽  
Ecological Factors ◽  
Survival Strategies ◽  
Genetic Connectivity ◽  
Spatial And Temporal Variability ◽  
Gene Pools ◽  
Aquaculture Ponds ◽  
Genetic Differentiation Of Populations ◽  
The Many ◽  
Private Alleles

Lagoonal environments exhibit high levels of instability depending on hydrological, climatic and ecological factors, thereby influencing the distribution and structure of submerged plant communities. Conditions typically fluctuate widely due to the interaction of freshwater from rivers with saltwater from the sea, as well as from aquaculture activities that together influence submerged hydrophyte community spatial and temporal variability depending on plant survival strategies. Ruppia species feature either underwater pollination mediated by an air bubble or by the release of pollen floating at the water surface, the former promoting self-pollination. Tropical Asian Ruppia brevipedunculata Yu and den Hartog was assumed to pollinate below the water surface and identified as a separate lineage among selfed Ruppia taxa. We used nine nuclear microsatellites to estimate inbreeding levels and connectivity of R. brevipedunculata within a large SE Asian lagoon complex. Ruppia brevipedunculata meadows were strongly inbred as could be derived from the many monomorphic or totally fixed loci for unique alleles in different parts of the lagoon, which appears consistent with selfing behavior. Those from aquaculture ponds were highly inbred (FIS = 0.620), though less than open lagoon sites that showed nearly total inbreeding (FIS = 0.942). Ruppia brevipedunculata from two major lagoon parts were highly differentiated with spatially structured gene pools and a strong barrier between parts of the lagoon over a 30 km distance. Migration-n analysis indicated unidirectional though limited gene flow and following potential hydrological connectivity. Overall, private alleles under homozygote conditions explained a stronger genetic differentiation of populations situated inside aquaculture ponds than of open lagoon populations. Kinship values were only relevant up to 5 km distance in the open lagoon. Within a confined area of aquaculture ponds featuring dense vegetation in stagnant water, there would be opportunity for mixed pollination, thereby explaining the higher diversity of unique multilocus genotypes of aquaculture pond habitats. Low connectivity prevents gene pools to homogenize however promoted sites with private alleles across the lagoon. Complex hydrodynamic systems and human-made habitats enclosed by physical structures impose barriers for propagule dispersal though may create refugia and contribute to conserving regional genetic diversity.

LA Psychiatrie Familiale, Les Systemes Transactionnels, Et Les Frontieres De La Pedopsychiatrie

1975 ◽  
Vol 20 (2) ◽  
pp. 151-155
Author(s):  
Martin L. Solomon
Keyword(s):  
Child Psychiatry ◽  
Role Theory ◽  
Social Role ◽  
Open Systems ◽  
Ecological Factors ◽  
General System ◽  
Psychiatric Training ◽  
Communications Theory ◽  
Integrated Concept ◽  
The Many

Family therapists, seen as emphasizing interventions leading to change in family structure and in sequences of behaviour, have been searching for an integrated concept which transactional systems theory seems to offer. It takes into account small group theory, social role theory, communications theory, and general system theory, which are linked to psychic, somatic, socio-cultural, politico-economic, and ecological factors. This idea of interlinked, open systems which influence each other is used as a viewpoint for examining the frontiers of child psychiatry. Adult patients often have children who are affected by their parents’ treatment, and child psychiatrists often intervene with adults. Similarly, the boundaries between psychiatry and the paramedical professions have grown less distinct as we have become aware of more elements to assess in each case, and as the number of therapeutic techniques and possible interventions increase. The problem of defining child psychiatry is discussed, as is psychiatric training, in terms of the difficulty in integrating the many theoretical and practical levels.

scholarly journals Surface Heat Budget estimation for Laurance Lake, US

2021 ◽  
Vol 877 (1) ◽  
pp. 012005
Author(s):  
Dahlia S. Abed-Zaid ◽  
Hussein A. M. Al-Zubaidi
Keyword(s):  
Surface Temperature ◽  
Water Surface ◽  
Heat Budget ◽  
Meteorological Data ◽  
Longwave Radiation ◽  
Atmospheric Conditions ◽  
Large Lakes ◽  
Water Surface Temperature ◽  
Maximum Water ◽  
The Many

Abstract Estimating heat budget factors are important to understand the many physical processes of large lakes and their reaction to the atmosphere. Some of these components are affected by water temperature, while the other depends on atmospheric conditions. This paper estimates the total heat flux for Lawrence lake via a code developed in MATLAB environment. The code can deal with different time resolutions if the lake water surface temperature data were at different time resolutions from the meteorological data. Results showed that solar energy peaks at 842 Watt/m2 at 540 Julian day, which is very normal for a sunny summer day, while the longwave radiation has 204 Watt/m2 as a min value. The back radiation did not make any reaction for the variation, but it revealed a small gradient. Furthermore, evaporation recorded - 67 Watt/m2 as a minimum value at 659 Julian day and 360 Watt/m2 as a maximum value at 578.43 Julian day close to the maximum water surface temperature event.

The Institute of Evolution Wild Cereal Gene Bank at the University of Haifa

2018 ◽  
Vol 65 (3-4) ◽  
pp. 129-146 ◽  
Author(s):  
Tamar Krugman ◽  
Eviatar Nevo ◽  
Alex Beharav ◽  
Hanan Sela ◽  
Tzion Fahima
Keyword(s):  
Agronomic Traits ◽  
Natural Populations ◽  
Ecological Factors ◽  
Triticum Dicoccoides ◽  
Grain Protein Content ◽  
Hordeum Spontaneum ◽  
Gene Bank ◽  
Gene Pools ◽  
Wide Range ◽  
The University

The Institute of Evolution Wild Cereal Gene Bank (ICGB) at the University of Haifa, Israel, harbors extensive collections of wild emmer wheat (WEW), Triticum dicoccoides, and wild barley (WB), Hordeum spontaneum, the primary progenitors of wheat and barley, respectively. The ICGB also includes minor collections of 10 species of Aegilops, wild oat (Avena barbata), and Brachypodium stacei and B. hybridum (previously distachyon). Here, we describe the WEW and WB collections, explain sampling strategies, and introduce related studies. Natural populations were sampled across Israel along aridity gradients, occurring from north to south and from west to east, and in local microsites with variable (or contrasting) ecological factors. The collection sites varied greatly in terms of climatic (rainfall, temperature and humidity), edaphic (soil types), and topography (altitude, slope) variables. Thus, the ICGB collections represent wild cereals adapted to a wide range of habitats and eco-geographical conditions. We have collected and preserved these unique gene pools since mid-70th, and further used them for theoretical and applied studies in population genetics, evolution, domestication, adaptation to local and regional habitats, and coping mechanisms for a plethora of biotic and abiotic stresses. Our studies revealed that WEW and WB populations from Israel harbor high adaptive genetic diversity that can serve as a reservoir of beneficial alleles to improve important agronomic traits such as disease resistance, drought tolerance and improved grain protein content. These mostly untapped genetic resources could contribute to increasing world food production for the constantly rising human population.

scholarly journals Water circulation induced by mechanical aerators in a rectangular vessel for shrimp aquaculture

2018 ◽  
Author(s):  
Tomoaki Itano ◽  
Taishi Inagaki ◽  
Choji Nakamura ◽  
Ren Hashimoto ◽  
Naohiro Negoro ◽  
...  
Keyword(s):  
Water Surface ◽  
Shrimp Aquaculture ◽  
Water Current ◽  
Vertical Circulation ◽  
Current Field ◽  
Paddle Wheel ◽  
Advantages And Disadvantages ◽  
Direct Measurements ◽  
Aquaculture Ponds ◽  
Cost Efficient

A water streamer was designed for the purpose of enhancing cost-efficient circulative flow between the water surface and bottom in shrimp aquaculture ponds. We took direct measurements of the water current field induced by the designed aerator in a large rectangular reservoir of dimensions (L)50?(W)19?(D)1.3 m^3 and compared the results with those of a standard Taiwanese paddle-wheel aerator. Vertical circulation between the surface and the bottom induced by the paddle wheel aerator was smaller than that by the designed aerator. Furthermore, the paddle-wheel aerator consumed more electric power than the designed aerator. The structures of water current induced by the two aerators are elucidated, and the advantages and disadvantages of the aerators are discussed. Overall, the designed aerator was found to be more efficient than the standard aerator.

scholarly journals Assessing the capabilities of the Surface Water and Ocean Topography (SWOT) mission for large lake water surface elevation monitoring under different wind conditions

2020 ◽  
Vol 24 (12) ◽  
pp. 5985-6000
Author(s):  
Jean Bergeron ◽  
Gabriela Siles ◽  
Robert Leconte ◽  
Mélanie Trudel ◽  
Damien Desroches ◽  
...  
Keyword(s):  
Surface Water ◽  
Water Surface ◽  
Management Strategies ◽  
Water Volume ◽  
Spatial And Temporal Variability ◽  
Large Lakes ◽  
Spatial Coverage ◽  
Lake Hydrodynamics ◽  
Ocean Topography ◽  
Set Up

Abstract. Lakes are important sources of freshwater and provide essential ecosystem services. Monitoring their spatial and temporal variability, and their functions, is an important task within the development of sustainable water management strategies. The Surface Water and Ocean Topography (SWOT) mission will provide continuous information on the dynamics of continental (rivers, lakes, wetlands and reservoirs) and ocean water bodies. This work aims to contribute to the international effort evaluating the SWOT satellite (2022 launch) performance for water balance assessment over large lakes (e.g., >100 km2). For this purpose, a hydrodynamic model was set up over Mamawi Lake, Canada, and different wind scenarios on lake hydrodynamics were simulated. The derived water surface elevations (WSEs) were compared to synthetic elevations produced by the Jet Propulsion Laboratory (JPL) SWOT high resolution (SWOT-HR) simulator. Moreover, water storages and net flows were retrieved from different possible SWOT orbital configurations and synthetic gauge measurements. In general, a good agreement was found between the WSE simulated from the model and those mimicked by the SWOT-HR simulator. Depending on the wind scenario, errors ranged between approximately −2 and 5 cm for mean error and from 30 to 70 cm root mean square error. Low spatial coverage of the lake was found to generate important biases in the retrievals of water volume or net flow between two satellite passes in the presence of local heterogeneities in WSE. However, the precision of retrievals was found to increase as spatial coverage increases, becoming more reliable than the retrievals from three synthetic gauges when spatial coverage approaches 100 %, demonstrating the capabilities of the future SWOT mission in monitoring dynamic WSE for large lakes across Canada.

The toxicity of petroleum oils to birds

1993 ◽  
Vol 1 (2) ◽  
pp. 92-103 ◽  
Author(s):  
Frederick A. Leighton
Keyword(s):  
Reproductive Effort ◽  
Oil Pollution ◽  
Ecological Factors ◽  
Water Repellency ◽  
Bird Populations ◽  
Highly Sensitive ◽  
Oxidant Damage ◽  
Egg Shell ◽  
The Many ◽  
Petroleum Oils

Mortality of aquatic birds occurs regularly as a consequence of spills of petroleum oils. There are three different ways in which such oils can affect birds. (i) External contamination of feathers is the most common form of exposure, and the effect of oils on feathers is the single most devastating effect of oil on birds. Feathers absorb oil, become matted, and lose the critical properties of water repellency, insulation, and flight. Death results from combinations of hypothermia, starvation, and drowning. (ii) Avian embryos are highly sensitive to oil that contaminates the egg shell; amounts as little as 1–10 μL are lethal to embryos during the first half of incubation. (iii) Birds ingest oil when preening oiled plumage or ingesting oiled nutrients. At least three toxic effects of ingested oil are well documented: a nonspecific response as a stressor that is additive or synergistic with those of other stressors, impairments in reproduction ranging from lowered fertility to abandonment of reproductive effort, and severe oxidant damage to red blood cells. The effect of oil pollution on bird populations is very difficult to document and is likely to remain uncertain because of the many ecological factors that may occur in association with an oil-spill event.Key words: oil, petroleum, pollution, bird, toxicity, poison.

scholarly journals Conservation genomics of the threatened western spadefoot, Spea hammondii, in urbanized southern California

2020 ◽  
Author(s):  
Kevin M Neal ◽  
Robert N Fisher ◽  
Milan J Mitrovich ◽  
H Bradley Shaffer
Keyword(s):  
Los Angeles ◽  
Population Size ◽  
Effective Population Size ◽  
Southern California ◽  
Orange County ◽  
Genetic Connectivity ◽  
Gene Pools ◽  
Conservation Genomics ◽  
Effective Population ◽  
Artificial Ponds

Abstract Populations of the western spadefoot (Spea hammondii) in southern California occur in one of the most urbanized and fragmented landscapes on the planet and have lost up to 80% of their native habitat. Orange County is one of the last strongholds for this pond-breeding amphibian in the region, and ongoing restoration efforts targeting S. hammondii have involved habitat protection and the construction of artificial breeding ponds. These efforts have successfully increased breeding activity, but genetic characterization of the populations, including estimates of effective population size and admixture between the gene pools of constructed artificial and natural ponds, has never been undertaken. Using thousands of genome-wide single-nucleotide polymorphisms, we characterized the population structure, genetic diversity, and genetic connectivity of spadefoots in Orange County to guide ongoing and future management efforts. We identified at least two, and possibly three major genetic clusters, with additional substructure within clusters indicating that individual ponds are often genetically distinct. Estimates of landscape resistance suggest that ponds on either side of the Los Angeles Basin were likely interconnected historically but intense urban development has rendered them essentially isolated, and the resulting risk of interruption to natural metapopulation dynamics appears to be high. Resistance surfaces show that the existing artificial ponds were well-placed and connected to natural populations by low-resistance corridors. Toad samples from all ponds (natural and artificial) returned extremely low estimates of effective population size, possibly due to a bottleneck caused by a recent multi-year drought. Management efforts should focus on maintaining gene flow among natural and artificial ponds by both assisted migration and construction of new ponds to bolster the existing pond network in the region.

The Many Faces of Authoritarian Persistence: A Set-Theory Perspective on the Survival Strategies of Authoritarian Regimes

2018 ◽  
Vol 55 (1) ◽  
pp. 64-87 ◽  
Author(s):  
Seraphine F. Maerz
Keyword(s):  
Comparative Analysis ◽  
Set Theory ◽  
Fuzzy Set ◽  
Qualitative Comparative Analysis ◽  
Authoritarian Regimes ◽  
Survival Strategies ◽  
Causal Relations ◽  
The Many ◽  
Authoritarian Survival ◽  
Causal Complexity

AbstractThis article examines how authoritarian regimes combine various strategies of repression, co-optation and legitimation to remain in power. The contribution of the article is two-fold. First, I conceptualize the hexagon of authoritarian persistence as a framework to explain how authoritarian regimes manage to survive. The hexagon is based on Gerschewski’s (2013) three pillars of stability but proposes some crucial modifications. In contrast to the model of the three pillars, the hexagon can grasp the causal complexity of autocratic survival because it is rooted in set theory and accounts for asymmetric causal relations, conjunctural causation and equifinality. Based on this, it illuminates how authoritarian regimes use multiple, mutually non-exclusive survival strategies. The second contribution is an empirical exploration which applies the hexagon and provides a case-oriented analysis of 62 persistent and non-persistent authoritarian regimes (1991–2010). By using fuzzy-set qualitative comparative analysis, the findings of this assessment illustrate five configurations of the hexagon – called hegemonic, performance-dependent, rigid, overcompensating and adaptive authoritarianism – as those combinations of strategies which facilitate authoritarian survival.

scholarly journals Assessing the capabilities of the SWOT mission for large lake water surface elevation monitoring under different wind conditions

2020 ◽  
Author(s):  
Jean Bergeron ◽  
Gabriela Siles ◽  
Robert Leconte ◽  
Mélanie Trudel ◽  
Damien Desroches ◽  
...  
Keyword(s):  
Water Surface ◽  
Management Strategies ◽  
Water Volume ◽  
Spatial And Temporal Variability ◽  
Large Lakes ◽  
Spatial Coverage ◽  
Lake Hydrodynamics ◽  
Ocean Topography ◽  
Set Up ◽  
Net Flows

Abstract. Lakes are important sources of freshwater and provide essential ecosystem services. Monitoring their spatial and temporal variability, as well as of their functions, is an important task within the development of sustainable water management strategies. The Surface Water and Ocean Topography (SWOT) mission will provide continuous information on the dynamics of continental (rivers, lakes, wetlands and reservoirs) and ocean water bodies. This work aims to contribute to the international effort evaluating the SWOT satellite (2022 launch) performance for water balance assessment over large lakes (e.g., > 100 km2). For this purpose, a hydrodynamic model was set up over Mamawi Lake, Canada, and different wind scenarios on lake hydrodynamics were simulated. The derived water surface elevations (WSE) were compared to synthetic elevations produced by the Jet Propulsion Laboratory (JPL) SWOT high resolution (SWOT-HR) simulator. Moreover, water storages and net flows were retrieved from different possible SWOT orbital configurations, as well as synthetic gauge measurements. In general, a good agreement was found between the WSE simulated from the model and those mimicked by the SWOT-HR simulator. Depending on the wind scenario, errors ranged between approximately −2 and 5 cm for mean error, and 30 to 70 cm root mean square error. Low spatial coverage of the lake was found to generate important biases in the retrievals of water volume or net flow between two satellite passes in the presence of local heterogeneities in WSE. However, the precision of retrievals was found to increase as spatial coverage increases, becoming more reliable than the retrievals from 3 synthetic gauges when spatial coverage approaches 100 %, demonstrating the capabilities of the future SWOT mission in monitoring dynamic WSE for large lakes across Canada.

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