scholarly journals Pygoscelid penguins breeding distribution and population trends at Lions Rump rookery, King George Island

2013 ◽  
Vol 34 (1) ◽  
pp. 87-99 ◽  
Author(s):  
Małgorzata Korczak−Abshire ◽  
Michał Węgrzyn ◽  
Piotr J. Angiel ◽  
Maja Lisowska
Keyword(s):  
Environmental Changes ◽  
King George Island ◽  
Time Intervals ◽  
Breeding Populations ◽  
Population Sizes ◽  
Natural Response ◽  
Gis System ◽  
The Antarctic ◽  
Pygoscelid Penguins

AbstractLong term changes (46 years) in the abundance of pygoscelid penguins breeding populations and nests distribution in the Lions Rump (King George Island) colony were in− vestigated in three time intervals, according to previously published two censuses and one original study conducted in 2010. At that time a detailed colony map based on the GIS system was made. Results of this study showed different trends for each investigated species. In the last three decades Adélie penguin breeding populations showed strong declining tendencies (69.61%). In contrast, the population of gentoo penguins represents the reverse trend, increasing 171.85% over the same period. Observed changes in both penguin population sizes are reflected in the different spatial and geographic distribution of their nests. The population changes observed at the Lions Rump colony are consistent with the relevant pygoscelid penguin tendencies in the western Antarctic Peninsula region. Breeding penguin population dynamics at Lions Rump area with a minimal disturbance by human activity may well illustrate a natural response of those birds to environmental changes in the Antarctic.

scholarly journals Antarctic Studies Show Lichens to be Excellent Biomonitors of Climate Change

Diversity ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 42 ◽  
Author(s):  
Leopoldo Sancho ◽  
Ana Pintado ◽  
T. Green
Keyword(s):  
Climate Change ◽  
Air Pollution ◽  
Growth Rate ◽  
Latitudinal Gradient ◽  
Environmental Changes ◽  
Mean Annual Temperature ◽  
Polar Regions ◽  
Time Intervals ◽  
Short Time ◽  
The Antarctic

Lichens have been used as biomonitors for multiple purposes. They are well-known as air pollution indicators around urban and industrial centers. More recently, several attempts have been made to use lichens as monitors of climate change especially in alpine and polar regions. In this paper, we review the value of saxicolous lichens for monitoring environmental changes in Antarctic regions. The pristine Antarctica offers a unique opportunity to study the effects of climate change along a latitudinal gradient that extends between 62° and 87° S. Both lichen species diversity and thallus growth rate seem to show significant correlations to mean annual temperature for gradients across the continent as well as to short time climate oscillation in the Antarctic Peninsula. Competition interactions appear to be small so that individual thalli develop in balance with environmental conditions and, as a result, can indicate the trends in productivity for discrete time intervals over long periods of time.

scholarly journals Differential responses of marine communities to natural and anthropogenic changes

2015 ◽  
Vol 282 (1803) ◽  
pp. 20142990 ◽  
Author(s):  
Michał Kowalewski ◽  
Jacalyn M. Wittmer ◽  
Troy A. Dexter ◽  
Alessandro Amorosi ◽  
Daniele Scarponi
Keyword(s):  
Environmental Changes ◽  
Species Turnover ◽  
Homogeneous System ◽  
Turnover Rates ◽  
Time Intervals ◽  
Northern Adriatic ◽  
Marine Communities ◽  
Ecosystem Shift ◽  
Natural Climate

Responses of ecosystems to environmental changes vary greatly across habitats, organisms and observational scales. The Quaternary fossil record of the Po Basin demonstrates that marine communities of the northern Adriatic re-emerged unchanged following the most recent glaciation, which lasted approximately 100 000 years. The Late Pleistocene and Holocene interglacial ecosystems were both dominated by the same species, species turnover rates approximated predictions of resampling models of a homogeneous system, and comparable bathymetric gradients in species composition, sample-level diversity, dominance and specimen abundance were observed in both time intervals. The interglacial Adriatic ecosystems appear to have been impervious to natural climate change either owing to their persistence during those long-term perturbations or their resilient recovery during interglacial phases of climate oscillations. By contrast, present-day communities of the northern Adriatic differ notably from their Holocene counterparts. The recent ecosystem shift stands in contrast to the long-term endurance of interglacial communities in face of climate-driven environmental changes.

Testing theoretical metapopulation conditions with genotypic data from Boreal Chorus Frogs (Pseudacris maculata)

2019 ◽  
Vol 97 (11) ◽  
pp. 1042-1053
Author(s):  
Shawn M. Billerman ◽  
Brett R. Jesmer ◽  
Alexander G. Watts ◽  
Peter E. Schlichting ◽  
Marie-Josée Fortin ◽  
...  
Keyword(s):  
Demographic Data ◽  
Methodological Framework ◽  
Effective Population ◽  
Pseudacris Maculata ◽  
Breeding Populations ◽  
Chorus Frogs ◽  
Population Sizes ◽  
Feasible Alternative ◽  
Landscape Genetic

The metapopulation concept has far-reaching implications in ecology and conservation biology. Hanski’s criteria operationally define metapopulations, yet testing them is hindered by logistical and financial constraints inherent to the collection of long-term demographic data. Hence, ecologists and conservationists often assume metapopulation existence for dispersal-limited species that occupy patchy habitats. To advance understanding of metapopulation theory and improve conservation of metapopulations, we used population and landscape genetic tools to develop a methodological framework for evaluating Hanski’s criteria. We used genotypic data (11 microsatellite loci) from a purported metapopulation of Boreal Chorus Frogs (Pseudacris maculata (Agassiz, 1850)) in Colorado, U.S.A., to test Hanski’s four criteria. We found support for each criterion: (1) significant genetic differentiation between wetlands, suggesting distinct breeding populations; (2) wetlands had small effective population sizes and recent bottlenecks, suggesting populations do not experience long-term persistence; (3) population graphs provided evidence of gene flow between patches, indicating potential for recolonization; and (4) multiscale bottleneck analyses suggest asynchrony, indicating that simultaneous extinction of all populations was unlikely. Our methodological framework provides a logistically and financially feasible alternative to long-term demographic data for identifying amphibian metapopulations.

Demography and reproductive ecology of the Columbia spotted frog (Rana luteiventris) across the Palouse

2005 ◽  
Vol 83 (5) ◽  
pp. 702-711 ◽  
Author(s):  
Abbey B Davis ◽  
Paul A Verrell
Keyword(s):  
Population Size ◽  
Reproductive Ecology ◽  
Small Population ◽  
Effective Population ◽  
Small Population Size ◽  
Rana Luteiventris ◽  
Breeding Populations ◽  
The Status ◽  
Population Sizes

Here we report on the demography and reproductive ecology of the Columbia spotted frog (Rana luteiventris Thompson, 1913) breeding in ponds across the Palouse Bioregion of Washington and Idaho. Spotted frogs are unusual, if not unique, among temperate ranids in that males establish the oviposition site before females become active. Females laid at one or two communal sites in shallow water. Our breeding populations were small, never exceeding 50 adults counted, and most displayed male-biased sex ratios. We estimated effective population sizes (Ne) as ranges determined by extremes in male breeding success; these varied between 3.2 and 37.8. Even the latter falls below the minimum required for long-term population viability. Small population size may make spotted frogs vulnerable to genetic problems and environmental insults. Communal oviposition certainly renders a population's reproductive effort vulnerable to variation in hydroperiod, which we observed during the dry spring of 2004. In the absence of information on the degree of "connectedness" among our ponds as subunits of more resilient metapopulations, we suggest that small population size and communal oviposition likely render R. luteiventris vulnerable to anthropogenic disturbance. Furthermore, the status of R. luteiventris on the Palouse may be less secure than assumed currently.

scholarly journals Downscaling SSP-consistent global spatial urban land projections from 1/8-degree to 1-km resolution 2000–2100

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Jing Gao ◽  
Martino Pesaresi
Keyword(s):  
Data Science ◽  
Environmental Changes ◽  
Urban Land ◽  
Time Intervals ◽  
Spatial And Temporal Scales ◽  
Global Coverage ◽  
Urban Land Expansion ◽  
Using Data ◽  
Potential Interactions

AbstractLong-term, spatial urban land projections that simultaneously offer global coverage and local-scale empirical accuracy are rare. Recently a set of such projections was produced using data-science-based simulations and the Shared Socioeconomic Pathways (SSPs). These projections update at decadal time intervals from 2000 to 2100 with a spatial resolution of 1/8 degree, while many socio-environmental studies customarily run their analysis and modelling at finer spatial resolutions, e.g. 1-km. Here we develop and validate an algorithm to downscale the 1/8-degree spatial urban land projections to the 1-km resolution. The algorithm uses an iterative process to allocate the decadal amount of urban land expansion originally projected for each 1/8-degree grid to its constituent 1-km grids. The results are a set of global maps showing urban land fractions at the 1-km resolution, updated at decadal intervals from 2000 to 2100, under five different urban land expansion scenarios consistent with the SSPs. The data can support studies of potential interactions between future urbanization and environmental changes across spatial and temporal scales.

scholarly journals Changes in bird communities of Admiralty Bay, King George Island (West Antarctic): insights from monitoring data (1977–1996)

2017 ◽  
Vol 38 (2) ◽  
pp. 231-262 ◽  
Author(s):  
Kazimierz Sierakowski ◽  
Małgorzata Korczak-Abshire ◽  
Piotr Jadwiszczak
Keyword(s):  
Gentoo Penguin ◽  
King George Island ◽  
Admiralty Bay ◽  
Bird Populations ◽  
West Antarctic ◽  
Breeding Populations ◽  
Western Shore ◽  
Population Sizes ◽  
South Shetlands ◽  
Penguin Species

AbstractThe paper summarizes results of twenty years of seabird observations carried out between 1977 and 1996 on the western shore of Admiralty Bay (King George Island, South Shetlands, Antarctic). Changes in population size, distribution and phenology of the breeding species as well as the appearance of non-breeding species are reported. A total of 34 species of birds were observed, including 13 breeding species. Among the non-breeding species, four were observed to visit the site regularly, six rarely, and the remaining 11 were observed only occasionally. Among breeding populations, three Pygoscelis penguin species, the main krill consumers, were most numerous. The Adélie Penguin (P. adeliae) dominated among the penguins nesting in the investigated areas, reaching 23,661 breeding pairs in 1978. Two other penguin species were less abundant with population sizes of approximately 7,200 breeding pairs for the Chinstrap Penguin (P. antarcticus) and 3,100 breeding pairs for the Gentoo Penguin (P. papua) in the same year. During the following two decades, breeding populations of pygoscelid species experienced a declining trend and their numbers were reduced by 68.0% for Chinstrap, 67.1% for Gentoo, and 33.9% for Adélie Penguins. The data reported here represent a unique reference basis and provide valuable information about indicator species, suitable for comparison with contemporary observations of bird populations in the Antarctic Peninsula region, a place of rapidly occurring climate changes and intensive harvesting of marine living resources.

Designing a CRM Framework for online & offline sports footwear retailers

2015 ◽  
Vol 3 (1) ◽  
Author(s):  
Rodrigo Cueva ◽  
Guillem Rufian ◽  
Maria Gabriela Valdes
Keyword(s):  
Environmental Changes ◽  
Customer Relationship ◽  
Business Strategies ◽  
Economic Sectors ◽  
Running Shoes ◽  
Brick And Mortar ◽  
Key Factor ◽  
On Line ◽  
The Impact

The use of Customer Relationship Managers to foster customers loyalty has become one of the most common business strategies in the past years.  However, CRM solutions do not fill the abundance of happily ever-after relationships that business needs, and each client’s perception is different in the buying process.  Therefore, the experience must be precise, in order to extend the loyalty period of a customer as much as possible. One of the economic sectors in which CRM’s have improved this experience is retailing, where the personalized attention to the customer is a key factor.  However, brick and mortar experiences are not enough to be aware in how environmental changes could affect the industry trends in the long term.  A base unified theoretical framework must be taken into consideration, in order to develop an adaptable model for constructing or implementing CRMs into companies. Thanks to this approximation, the information is complemented, and the outcome will increment the quality in any Marketing/Sales initiative. The goal of this article is to explore the different factors grouped by three main domains within the impact of service quality, from a consumer’s perspective, in both on-line and off-line retailing sector.  Secondly, we plan to go a step further and extract base guidelines about previous analysis for designing CRM’s solutions focused on the loyalty of the customers for a specific retailing sector and its product: Sports Running Shoes.

Past testate amoeba communities in landslide mountain fens (Polish Carpathians): The relationship between shell types and sediment

The Holocene ◽  
2021 ◽  
pp. 095968362199464
Author(s):  
Katarzyna Marcisz ◽  
Krzysztof Buczek ◽  
Mariusz Gałka ◽  
Włodzimierz Margielewski ◽  
Matthieu Mulot ◽  
...  
Keyword(s):  
Environmental Changes ◽  
Testate Amoebae ◽  
Mineral Matter ◽  
Testate Amoeba ◽  
Run Off ◽  
Number Of Factors ◽  
Depth To Water Table ◽  
Polish Carpathians ◽  
The Relationship

Landslide mountain fens formed in landslide depressions are dynamic environments as their development is disturbed by a number of factors, for example, landslides, slopewash, and surface run-off. These processes lead to the accumulation of mineral material and wood in peat. Disturbed peatlands are interesting archives of past environmental changes, but they may be challenging for providing biotic proxy-based quantitative reconstructions. Here we investigate long-term changes in testate amoeba communities from two landslide mountain fens – so far an overlooked habitat for testate amoeba investigations. Our results show that abundances of testate amoebae are extremely low in this type of peatlands, therefore not suitable for providing quantitative depth-to-water table reconstructions. However, frequent shifts of dominant testate amoeba species reflect dynamic lithological situation of the studied fens. We observed that high and stable mineral matter input into the peatlands was associated with high abundances of species producing agglutinated (xenosomic) as well as idiosomic shells which prevailed in the testate amoeba communities in both analyzed profiles. This is the first study that explores testate amoebae of landslide mountain fens in such detail, providing novel information about microbial communities of these ecosystems.

scholarly journals Mass balance of the Antarctic ice sheet 1992–2016: reconciling results from GRACE gravimetry with ICESat, ERS1/2 and Envisat altimetry

2021 ◽  
pp. 1-27
Author(s):  
H. Jay Zwally ◽  
John W. Robbins ◽  
Scott B. Luthcke ◽  
Bryant D. Loomis ◽  
Frédérique Rémy
Keyword(s):  
Mass Balance ◽  
Antarctic Peninsula ◽  
East Antarctica ◽  
Mantle Material ◽  
West Antarctica ◽  
Mantle Viscosity ◽  
Grounding Line ◽  
The Antarctic ◽  
Total Gain

Abstract GRACE and ICESat Antarctic mass-balance differences are resolved utilizing their dependencies on corrections for changes in mass and volume of the same underlying mantle material forced by ice-loading changes. Modeled gravimetry corrections are 5.22 times altimetry corrections over East Antarctica (EA) and 4.51 times over West Antarctica (WA), with inferred mantle densities 4.75 and 4.11 g cm−3. Derived sensitivities (Sg, Sa) to bedrock motion enable calculation of motion (δB0) needed to equalize GRACE and ICESat mass changes during 2003–08. For EA, δB0 is −2.2 mm a−1 subsidence with mass matching at 150 Gt a−1, inland WA is −3.5 mm a−1 at 66 Gt a−1, and coastal WA is only −0.35 mm a−1 at −95 Gt a−1. WA subsidence is attributed to low mantle viscosity with faster responses to post-LGM deglaciation and to ice growth during Holocene grounding-line readvance. EA subsidence is attributed to Holocene dynamic thickening. With Antarctic Peninsula loss of −26 Gt a−1, the Antarctic total gain is 95 ± 25 Gt a−1 during 2003–08, compared to 144 ± 61 Gt a−1 from ERS1/2 during 1992–2001. Beginning in 2009, large increases in coastal WA dynamic losses overcame long-term EA and inland WA gains bringing Antarctica close to balance at −12 ± 64 Gt a−1 by 2012–16.

scholarly journals Cellular stress signaling activates type-I IFN response through FOXO3-regulated lamin posttranslational modification

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Inah Hwang ◽  
Hiroki Uchida ◽  
Ziwei Dai ◽  
Fei Li ◽  
Teresa Sanchez ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Environmental Changes ◽  
Type I ◽  
Neurogenic Differentiation ◽  
Forkhead Box ◽  
Nuclear Lamin ◽  
Neural Stem Progenitor Cells ◽  
Subsequent Activation ◽  
Methyl Group Transfer

AbstractNeural stem/progenitor cells (NSPCs) persist over the lifespan while encountering constant challenges from age or injury related brain environmental changes like elevated oxidative stress. But how oxidative stress regulates NSPC and its neurogenic differentiation is less clear. Here we report that acutely elevated cellular oxidative stress in NSPCs modulates neurogenic differentiation through induction of Forkhead box protein O3 (FOXO3)-mediated cGAS/STING and type I interferon (IFN-I) responses. We show that oxidative stress activates FOXO3 and its transcriptional target glycine-N-methyltransferase (GNMT) whose upregulation triggers depletion of s-adenosylmethionine (SAM), a key co-substrate involved in methyl group transfer reactions. Mechanistically, we demonstrate that reduced intracellular SAM availability disrupts carboxymethylation and maturation of nuclear lamin, which induce cytosolic release of chromatin fragments and subsequent activation of the cGAS/STING-IFN-I cascade to suppress neurogenic differentiation. Together, our findings suggest the FOXO3-GNMT/SAM-lamin-cGAS/STING-IFN-I signaling cascade as a critical stress response program that regulates long-term regenerative potential.

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