scholarly journals Latitudinal Variation into the Macrofaunal Assemblages Associated to Zostera noltei Seagrass along the Atlantic Coast of Morocco

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Oussama Bououarour ◽  
Soilam Boutoumit ◽  
Reda El Kamcha ◽  
Hocein Bazairi
Keyword(s):  
Large Scale ◽  
Atlantic Coast ◽  
Benthic Fauna ◽  
Marine Conservation ◽  
Latitudinal Variation ◽  
Anthropogenic Factors ◽  
Seagrass Beds ◽  
Benthic Assemblages ◽  
Zostera Noltei ◽  
Broad Scale

Large-scale research on seagrass-associated benthic fauna is very important for future regional marine conservation. In our study, we investigated spatial and latitudinal variation of benthic macroinvertebrate assemblages associated to Zostera noltei Hornemann, 1832 beds from five semi-enclosed coastal systems (SECSs) ranging from 23°N to 34°N along the Atlantic coast of Morocco. Overall, 17,320 individuals were reported as belonging to 96 taxa. The ecological community descriptors differ significantly at the level of the site. Specific richness showed an inconsistent significant pattern with latitude. The multivariate analyses of the assemblage’s composition showed 57% of total variation observed in benthic assemblages, while the PERMANOVA analysis confirmed that this variation is significant at the level of the site. According to DistLM results, variations in belowground biomass, and percentage of mud, were the important predictor variables explaining this variation along the large scale of the studied SECS. However, such patterns could be related to other factors such as habitat heterogeneity and regional, biogeographic, and anthropogenic factors. The present study marked the first attempt on broad-scale ecological research of seagrass beds in Morocco and offers baseline data for planning the broad-scale conservation of biodiversity in seagrass beds that remain suffering from multiple human-induced threats such as coastal developments and climate change.

scholarly journals Phylogeography in an “oyster” shell provides first insights into the genetic structure of an extinct Ostrea edulis population

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Sarah Hayer ◽  
Dirk Brandis ◽  
Alexander Immel ◽  
Julian Susat ◽  
Montserrat Torres-Oliva ◽  
...  
Keyword(s):  
Large Scale ◽  
Wadden Sea ◽  
Atlantic Coast ◽  
Phylogenetic Reconstruction ◽  
Oyster Shell ◽  
Glacial Refugia ◽  
Late Nineteenth Century ◽  
Ostrea Edulis ◽  
Geographic Ranges ◽  
The North

AbstractThe historical phylogeography of Ostrea edulis was successfully depicted in its native range for the first time using ancient DNA methods on dry shells from museum collections. This research reconstructed the historical population structure of the European flat oyster across Europe in the 1870s—including the now extinct population in the Wadden Sea. In total, four haplogroups were identified with one haplogroup having a patchy distribution from the North Sea to the Atlantic coast of France. This irregular distribution could be the result of translocations. The other three haplogroups are restricted to narrow geographic ranges, which may indicate adaptation to local environmental conditions or geographical barriers to gene flow. The phylogenetic reconstruction of the four haplogroups suggests the signatures of glacial refugia and postglacial expansion. The comparison with present-day O. edulis populations revealed a temporally stable population genetic pattern over the past 150 years despite large-scale translocations. This historical phylogeographic reconstruction was able to discover an autochthonous population in the German and Danish Wadden Sea in the late nineteenth century, where O. edulis is extinct today. The genetic distinctiveness of a now-extinct population hints at a connection between the genetic background of O. edulis in the Wadden Sea and for its absence until today.

scholarly journals Effects of a 5-year trawling ban on the local benthic community in a wind farm in the Dutch coastal zone

2014 ◽  
Vol 72 (3) ◽  
pp. 962-972 ◽  
Author(s):  
Magda J. N. Bergman ◽  
Selma M. Ubels ◽  
Gerard C. A. Duineveld ◽  
Erik W. G. Meesters
Keyword(s):  
Coastal Zone ◽  
Benthic Community ◽  
Large Scale ◽  
Wind Farm ◽  
Diversity Index ◽  
Benthic Assemblages ◽  
The North ◽  
Wiener Diversity Index ◽  
Short Period ◽  
Reference Areas

Abstract As part of a large impact study in a wind farm (OWEZ) in the Dutch coastal zone, the effects of exclusion of bottom trawling on the benthic community were studied by comparison with nearby reference areas which were regularly fished. In addition to a standard boxcorer for common macrofauna, a Triple-D dredge was used to collect longer-lived, more sparsely distributed infauna and epifauna. Multivariate analysis did not reveal any difference between the assemblages in and outside OWEZ with respect to abundance, biomass, and production after a 5-year closure. The Shannon–Wiener diversity index pointed to a significantly higher diversity in OWEZ compared with some of the reference areas. A minority of the bivalve species assumed to be sensitive to trawling showed higher abundances (Spisula solida) or larger sizes (Tellina fabula, Ensis directus) in OWEZ than in some of the reference areas. In general, samples collected with the Triple-D showed more differences between areas than boxcore samples. No evidence was also found that the species composition in OWEZ relative to the reference areas had changed in the period between 1 (2007) and 5 (2011) years after closure. The change observed in all areas between 2007 and 2011 was mainly due to relatively small variations in species abundances. In conclusion, 5 years after the closure of OWEZ to fisheries, only subtle changes were measured in the local benthic community, i.e. a higher species diversity and an increased abundance and lengths of some bivalves. Depleted adult stocks, faunal patchiness, and a limited time for recovery (5 years) might explain that a significant recovery could not be found. The current study shows that designation of large-scale marine protected areas as planned for the North Sea will not automatically imply that restoration of benthic assemblages can be expected within a relatively short period of years.

scholarly journals Explaining the trends and variability in the United States tornado records using climate teleconnections and shifts in observational practices

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Niloufar Nouri ◽  
Naresh Devineni ◽  
Valerie Were ◽  
Reza Khanbilvardi
Keyword(s):  
Population Density ◽  
Large Scale ◽  
Southern Oscillation ◽  
The United States ◽  
Anthropogenic Factors ◽  
Climate Variables ◽  
Term Trend ◽  
Cyclical Variability ◽  
Long Term Trend

AbstractThe annual frequency of tornadoes during 1950–2018 across the major tornado-impacted states were examined and modeled using anthropogenic and large-scale climate covariates in a hierarchical Bayesian inference framework. Anthropogenic factors include increases in population density and better detection systems since the mid-1990s. Large-scale climate variables include El Niño Southern Oscillation (ENSO), Southern Oscillation Index (SOI), North Atlantic Oscillation (NAO), Pacific Decadal Oscillation (PDO), Arctic Oscillation (AO), and Atlantic Multi-decadal Oscillation (AMO). The model provides a robust way of estimating the response coefficients by considering pooling of information across groups of states that belong to Tornado Alley, Dixie Alley, and Other States, thereby reducing their uncertainty. The influence of the anthropogenic factors and the large-scale climate variables are modeled in a nested framework to unravel secular trend from cyclical variability. Population density explains the long-term trend in Dixie Alley. The step-increase induced due to the installation of the Doppler Radar systems explains the long-term trend in Tornado Alley. NAO and the interplay between NAO and ENSO explained the interannual to multi-decadal variability in Tornado Alley. PDO and AMO are also contributing to this multi-time scale variability. SOI and AO explain the cyclical variability in Dixie Alley. This improved understanding of the variability and trends in tornadoes should be of immense value to public planners, businesses, and insurance-based risk management agencies.

A Multi-proxy assessment of the impact of climate change on Late Holocene (ca 4500-3800 BP) Native American villages of the Georgia coast

2021 ◽  
Author(s):  
Carey James Garland ◽  
Victor D Thompson ◽  
Matthew C Sanger ◽  
Karen Y Smith ◽  
Fred T Andrus ◽  
...  
Keyword(s):  
Native American ◽  
Environmental Change ◽  
Large Scale ◽  
Atlantic Coast ◽  
Archaic Period ◽  
Late Archaic ◽  
Shell Ring ◽  
Shell Rings ◽  
Georgia Coast ◽  
The Impact

Circular shell rings along the Atlantic Coast of southeastern North America are the remnants of some of the earliest villages that emerged during the Late Archaic Period (5000 – 3000 BP). Many of these villages, however, were abandoned during the Terminal Late Archaic Period (ca 3800 – 3000 BP). Here, we combine Bayesian chronological modeling with multiple environmental proxies to understand the nature and timing of environmental change associated with the emergence and abandonment of shell ring villages on Sapleo Island, Georgia. Our Bayesian models indicate that Native Americans occupied the three Sapelo shell rings at varying times with some generational overlap. By the end of the complex’s occupation, only Ring III was occupied before abandonment ca. 3845 BP. Ring III also consists of statistically smaller oysters ( Crassostrea virginica ) that people harvested from less saline estuaries compared to earlier occupations. These data, when integrated with recent tree ring analyses, show a clear pattern of environmental instability throughout the period in which the rings were occupied. We argue that as the climate became unstable around 4300 BP, aggregation at shell ring villages provided a way to effectively manage fisheries that are highly sensitive to environmental change. However, with the eventual collapse of oyster fisheries and subsequent rebound in environmental conditions ca. 3800 BP, people dispersed from shell rings, and shifted to non-marine subsistence economies and other types of settlements. This study provides the most comprehensive evidence correlations between large-scale environmental change and societal transformations on the Georgia coast during the Late Archaic period.

scholarly journals A Survey on Data Anonymization Using Mapreduce on Cloud with Scalable Two-Phase Top-Down Approach

2018 ◽  
Vol 7 (2.20) ◽  
pp. 254
Author(s):  
M Dhasaratham ◽  
R P. Singh
Keyword(s):  
Large Scale ◽  
Public Information ◽  
Top Down ◽  
Two Phase ◽  
Data Anonymization ◽  
Security Issues ◽  
Cloud Applications ◽  
Massive Information ◽  
Broad Scale

Endless forces anticipate that customers can cut non-public information like electronic prosperity records for information examination or mining, transferral security issues. Anonymizing instructional accumulations by ways for hypothesis to satisfy bound assurance necessities, parenthetically, k-anonymity may be a for the foremost half used arrangement of security shielding frameworks. At appear, the live of information in varied cloud applications augments massively consistent with the massive information slant, on these lines creating it a take a look at for habitually used programming instruments to confine, supervise, and method such large scale information within an appropriate snuck hobby. during this manner, it's a take a look at for existing anonymization approaches to manage accomplish security preservation on insurance sensitive monumental scale instructive files as a results of their insufficiency of skillfulness. during this paper, we have a tendency to propose a versatile 2 part top-down specialization (TDS) to anonymize broad scale instructive accumulations victimisation the MapReduce structure on cloud. In mboth times of our approach, we have a tendency to advisedly layout a affair of innovative MapReduce occupations to determinedly accomplish the specialization reckoning in an awfully versatile means. wildcat assessment happens demonstrate that with our approach, the flexibleness and adequacy of TDS may be basically redesigned over existing philosophies.  

scholarly journals Characterization of a resilient seagrass meadow during a decline period

2018 ◽  
Vol 82 (1) ◽  
pp. 67 ◽  
Author(s):  
Bárbara Ondiviela ◽  
Lina Fernández ◽  
Araceli Puente ◽  
Gerardo García-Castrillo ◽  
José A. Juanes
Keyword(s):  
Seagrass Meadow ◽  
Large Population ◽  
Sea Surface ◽  
Biological Traits ◽  
Benthic Assemblages ◽  
Biomass Density ◽  
Zostera Noltei ◽  
Poor Understanding ◽  
Freshwater Influence

Seagrasses are globally threatened ecosystems with essential ecological roles. An important limitation in seagrass conservation efforts is the poor understanding of resilient meadows. The present work studies a meadow, which maintained a large population of Zostera marina and Zostera noltei, during the decline of seagrasses in the Bay of Santander (from 1984 to 2000). The work examines resilience parameters related to the biological traits (biomass, density, length and width of the leaves) and to the associated benthic assemblages. The maturity of the meadow and the changing environmental conditions induced by the torrential regime of the Miera River, have likely improved the resistance to the periods of stress. The adaptation to these fluctuating conditions is reflected in a high seasonal and spatial variability in the biomass, density, morphological traits and benthic assemblages. These variations are related to the summer peaks in the PAR, the sea surface temperature and the freshwater influence along the discharge of the Miera River. This work provides the first seagrass data in Cantabria. The data are dated in the early 2000s and constitute a baseline study for the Bay of Biscay.

scholarly journals Body size information in large-scale acoustic bat databases

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5370 ◽  
Author(s):  
Caterina Penone ◽  
Christian Kerbiriou ◽  
Jean-François Julien ◽  
Julie Marmet ◽  
Isabelle Le Viol
Keyword(s):  
Body Size ◽  
Large Scale ◽  
Principal Component ◽  
Acoustic Signals ◽  
Species Traits ◽  
Climatic Variables ◽  
Characteristic Frequencies ◽  
Acoustic Data ◽  
Forearm Length ◽  
Broad Scale

Background Citizen monitoring programs using acoustic data have been useful for detecting population and community patterns. However, they have rarely been used to study broad scale patterns of species traits. We assessed the potential of acoustic data to detect broad scale patterns in body size. We compared geographical patterns in body size with acoustic signals in the bat species Pipistrellus pipistrellus. Given the correlation between body size and acoustic characteristics, we expected to see similar results when analyzing the relationships of body size and acoustic signals with climatic variables. Methods We assessed body size using forearm length measurements of 1,359 bats, captured by mist nets in France. For acoustic analyses, we used an extensive dataset collected through the French citizen bat survey. We isolated each bat echolocation call (n = 4,783) and performed automatic measures of signals, including the frequency of the flattest part of the calls (characteristic frequency). We then examined the relationship between forearm length, characteristic frequencies, and two components resulting from principal component analysis for geographic (latitude, longitude) and climatic variables. Results Forearm length was positively correlated with higher precipitation, lower seasonality, and lower temperatures. Lower characteristic frequencies (i.e., larger body size) were mostly related to lower temperatures and northern latitudes. While conducted on different datasets, the two analyses provided congruent results. Discussion Acoustic data from citizen science programs can thus be useful for the detection of large-scale patterns in body size. This first analysis offers a new perspective for the use of large acoustic databases to explore biological patterns and to address both theoretical and applied questions.

The Problem of Personality in Sapiozoi

2021 ◽  
pp. 39-42
Author(s):  
Irina A. Gerasimova ◽  
Keyword(s):  
Large Scale ◽  
Scientific Models ◽  
Anthropogenic Factors ◽  
Integrative Approach ◽  
Consumer Society ◽  
Quaternary Period ◽  
Global Crisis ◽  
Natural Systems ◽  
Global Factor ◽  
Planetary Processes

Article discusses the problem of personality in the coming era of Sapiozoic. In geochronology, the quaternary period (from 2.6 million years ago to the present) is called the epoch that gave rise to man (anthropogen). In the Holocene epoch (the last 12-thousand-year period), human economic activity is visible. At the same time, the planet’s ecosystems were in balance. Discussions are underway about the geologically transitional Anthropocene – the epoch of hu­man activity as a global factor in the evolution of the Earth’s ecosystems. During the last 200–250 years, the co-evolution of man, society and nature has been on the path of the formation of techno-natural systems. Since the 1950s and 1960s the era of “Great Acceleration” begins. Consumer society, unrestrained mining, the course of technologization, the loss of the meaning of life led to chaos on a planetary scale. Many natural scientists pointed out the anthropogenic factors of the new geological epoch. The parameters (and language of descrip­tion) of the Anthropocene that are put forward in the discussions are limited by the methodologies of specific disciplines. The philosophical-integrative approach to the problem is relevant. It is worth paying attention to non-Western philosoph­ical teachings about large cycles of planetary development. In part, they resem­ble the scientific models. The acceleration of planetary development and the new large-scale cycle are discussed in the Roerichs philosophy. Purification by the global crisis should lead to the disclosure of the spiritual potential of a person, the construction of a world community. In one scenario, the coming era of sus­tainable development is called “sapiozoi” – “intelligent life” (D. Grinspoon). Its essence is associated with the management of planetary processes. Geosocio­engineering projects in the cognitive aspect involve fundamental transformations of human consciousness as an active worker, the formation of planetary forms of collective cooperation. The strategic task of managing the Earth’s ecosystems re­quires the formation of cosmo-geo-bio-socio-human-dimensional thinking, noo­spheric ethics and noospheric culture. The problem of the mind and the inner na­ture of man becomes the key to overcoming the global crisis.

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