scholarly journals Fifteen years in a global warming hotspot: changes in subtidal mobile invertebrate communities

2020 ◽  
Vol 656 ◽  
pp. 227-238 ◽  
Author(s):  
YR Mulders ◽  
T Wernberg
Keyword(s):  
Global Warming ◽  
Latitudinal Gradient ◽  
Cumulative Effect ◽  
Lower Latitude ◽  
Size Distributions ◽  
Invertebrate Communities ◽  
Cool Temperate ◽  
Changes Over Time ◽  
Warm Temperate ◽  
Over Time

Temperate subtidal reefs are increasingly exposed to gradual warming and short periods of high temperatures (marine heatwaves; MHWs). These pressures can directly and indirectly affect the mobile invertebrate communities on these reefs. We investigate changes in mobile invertebrate communities from benthic surveys 15 yr apart (1999-2001 vs 2016-2019), spanning a 4° latitudinal gradient in Western Australia (30-34°S), expecting the biggest changes to the communities in the lower latitudes, where the cumulative effect of MHWs and warming is largest. The urchins Centrostephanus tenuispinus (warm temperate affinity) and Phyllacanthus irregularis (cool temperate affinity) showed trends toward opposite responses over time; while P. irregularis densities declined (non-significantly at all sites), C. tenuispinus densities increased (significantly at one of 3 sites). The magnitude of the responses appeared to decrease with increasing latitude, with C. tenuispinus recorded in significantly higher densities only at the lowest latitude location. Neither the densities, nor change in density over time of cool temperate gastropod Lunella torquatus and urchin Heliocidaris erythrogramma reflected a latitudinal gradient, suggesting other localized factors play a larger role in determining abundances of these species. However, size distributions of L. torquatus populations at the lower latitude locations were clearly impacted by the 2011 MHW, while those at higher latitudes remained relatively consistent. Overall, the biggest changes over time were seen at the warm edge of the temperate ecosystem. As temperatures continue to rise, the magnitude of these changes is not only expected to increase, but also to occur at higher latitudes.

Biodiversity and the biogeographic relationships of the Amphipoda: Gammaridea on the French coastline

2004 ◽  
Vol 84 (3) ◽  
pp. 621-628 ◽  
Author(s):  
Jean-Claude Dauvin ◽  
Denise Bellan-Santini
Keyword(s):  
Latitudinal Gradient ◽  
Marine Invertebrate ◽  
English Channel ◽  
Latitude Range ◽  
The North ◽  
North Eastern ◽  
Cool Temperate ◽  
Amphipoda Species ◽  
Central Atlantic ◽  
Warm Temperate

A recent inventory of the benthic Gammaridea: Amphipoda species on the French continental coastline catalogued 495 species. An analysis of the biodiversity and the biogeographic relationships that exist between the French Amphipoda: Gammaridea, living on the coastline that extends along 10° latitude range in the temperate region between 41° and 51° North and the other gammaridean faunas living in the north-eastern Atlantic has drawn the pattern of diversity in this marine invertebrate group on a large biogeographical scale. Gammaridean amphipods exhibit a latitudinal gradient over the total number of species, including the continental shelf species and the bathyal species. There are four main fauna groups, which correspond to the biogeographical zones of the north-eastern Atlantic: (1) a cold arctic and cool-temperate Svalbard and Norwegian coastal fauna; (2) a cool-temperate boreal and Boreal–Lusitanian United Kingdom, Irish and English Channel shallow fauna; (3) a warm-temperate Lusitanian Bay of Biscay and subtropical central Atlantic fauna; and (4) a subtropical Mediterranean fauna. The French fauna appears particularly rich, presenting 44% of the 1119 species recorded in the north-eastern Atlantic along the 50° latitude range (30°N–80°N).  This is obviously due to France's intermediate latitudinal location within the Lusitanian temperate biogeographical zone, which produces a biogeographical cross between the boreal fauna in the north and the warm temperate and sub-tropical fauna in the south.

scholarly journals Afrotropical montane birds experience upslope shifts and range contractions along a fragmented elevational gradient in response to global warming

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0248712
Author(s):  
Montague H. C. Neate-Clegg ◽  
Simon N. Stuart ◽  
Devolent Mtui ◽  
Çağan H. Şekercioğlu ◽  
William D. Newmark
Keyword(s):  
Global Warming ◽  
Bird Species ◽  
Bird Community ◽  
Elevational Gradient ◽  
Range Limits ◽  
Forest Fragments ◽  
Local Climate ◽  
Elevational Range ◽  
Changes Over Time ◽  
Over Time

Global warming is predicted to result in upslope shifts in the elevational ranges of bird species in montane habitats. Yet few studies have examined changes over time in the elevational distribution of species along fragmented gradients in response to global warming. Here, we report on a resurvey of an understory bird community in the Usambara Mountains in Tanzania, along a forested elevational gradient that has been fragmented over the last 200 years. In 2019, we resurveyed seven sites, ranging in elevation from 360 m to 2110 m, that were originally surveyed between 1979 and 1981. We calculated differences in mean elevation and lower and upper range limits for 29 species between the two time periods and corrected for possible differences in elevation due to chance. Over four decades, we documented a significant mean upslope shift across species of 93 m. This shift was smaller than the 125 m expected shift due to local climate warming. Of the 29 focal species, 19 shifted upslope, eight downslope, and two remained unchanged. Mean upslope shifts in species were driven largely by contracting lower range limits which moved significantly upslope on average across species by 183 m, while upper range limits shifted non-significantly upslope by 72 m, leading to a mean range contraction of 114 m across species. Community composition of understory bird species also shifted over time, with current communities resembling communities found historically at lower elevations. Past forest fragmentation in combination with the limited gap-crossing ability of many tropical understory bird species are very likely important contributory factors to the observed asymmetrical shifts in lower and upper elevational range limits. Re-establishing forested linkages among the largest and closest forest fragments in the Eastern Arc Mountains are critical to permitting species to shift upslope and to reduce further elevational range contractions over time.

scholarly journals 1325Longitudinal epidemiology of MS in the Greater Hobart region, 1961 to 2019

2021 ◽  
Vol 50 (Supplement_1) ◽  
Author(s):  
Steve Simpson-Yap ◽  
Roberts Atvar ◽  
Bruce Taylor
Keyword(s):  
Mortality Rate ◽  
Sex Ratio ◽  
Poisson Regression ◽  
Latitudinal Gradient ◽  
Mortality Rates ◽  
Data Sources ◽  
Lower Latitude ◽  
Incidence And Mortality ◽  
Crude Prevalence ◽  
Over Time

Abstract Background The Greater Hobart region (42.3°S) of Tasmania has the highest frequencies of MS in Australia, this consistent across studies conducted over the last half century. However, the degree of excess compared to mainland sites like Newcastle (32.5°S) has declined over time. Methods Cases were recruited from clinic-based samples and other multiple other data sources. Prevalence date was 1 June 2019. 2019 prevalence and 2009-19 incidence and mortality rates were estimated. Prevalence and incidence and mortality rates were age/sex-standardised to the 1961 and 1954 Hobart populations, respectively, to allow longitudinal comparisons. Female:male prevalence and incidence sex-ratios were also assessed. Differences between timepoints were assessed using Poisson regression. Results 472 MS cases (female:71.4%) resident on prevalence day were identified, a crude prevalence=212.3/100,000 (155.8 age/sex-standardised), 57% increase vs 2009 and 388.0% vs 1961. The 2009-19 incidence rate=7.56/100,000 person-years (7.03 age/sex-standardised), 91% increase vs 2001-9 and 218.1% vs 1951-61. The 2009-19 mortality rate was 2.25/100,000 person-years (1.12 age/sex-standardised), comparable to 2001-9 (1.00). The age/sex-standardised prevalence-sex-ratio was 2.61, comparable to 2009 (2.65), but the incidence-sex-ratio was 2.68, 31% increase vs 2001-9 (2.05). Conclusions Prevalence and incidence continue to be high in Hobart, although the differences compared to lower-latitude Newcastle have attenuated significantly. Changes in lifestyle may underlie the deterioration of the latitudinal gradient of MS in Australia. Further investigation is required to define the factors that drive these associations. Key messages MS prevalence and incidence are still highest in Australia in southern Tasmania but the latitudinal variation is declining.

Early Mesozoic phytogeography and climate

1993 ◽  
Vol 341 (1297) ◽  
pp. 297-305 ◽  
Keyword(s):  
Global Change ◽  
Climate Changes ◽  
Latitudinal Gradient ◽  
Middle Triassic ◽  
The Other ◽  
Late Triassic ◽  
Early Mesozoic ◽  
Regional Association ◽  
Cool Temperate ◽  
Warm Temperate

Triassic and Jurassic floral lists from Eurasia have been subjected to an ordination study. A latitudinal gradient is revealed for each interval of each epoch which can be interpreted climatically as ranging through the dry subtropical to the w arm and cool temperate biomes. Floras at the dry end of the spectrum may be identified by the dominance of microphyllous conifers and the regional association with evaporites. At the other extreme, the cool temperate floras are recognized by the abundance of deciduous ginkgophytes and broadleaved conifers. The highest diversity, centered at about 40° palaeolatitude, occurs in the intermediate w arm temperate zone which may contain all of the above floral elements in association with numerous fern and cycad genera. The transitions between these biomes remained at relatively constant latitudes, from the late Triassic to the early Cretaceous, suggesting climate stasis over a long interval. Climate changes, perceived locally, appear to be the result of continental motion rather than true global change. During the early and middle Triassic, however, the biomes are less distinct, with floras interpreted as warm temperate extending to latitudes of up to 70° north.

Comparison of two devices for measuring exercise transcutaneous oxygen pressures in patients with claudication

VASA ◽  
2015 ◽  
Vol 44 (5) ◽  
pp. 355-362 ◽  
Author(s):  
Marie Urban ◽  
Alban Fouasson-Chailloux ◽  
Isabelle Signolet ◽  
Christophe Colas Ribas ◽  
Mathieu Feuilloy ◽  
...  
Keyword(s):  
Oxygen Pressure ◽  
Optical Sensors ◽  
Chemical Sensors ◽  
Transcutaneous Oxygen ◽  
Starting Values ◽  
Two Systems ◽  
Transcutaneous Oxygen Pressure ◽  
New Sensors ◽  
Changes Over Time ◽  
Over Time

Abstract. Summary: Background: We aimed at estimating the agreement between the Medicap® (photo-optical) and Radiometer® (electro-chemical) sensors during exercise transcutaneous oxygen pressure (tcpO2) tests. Our hypothesis was that although absolute starting values (tcpO2rest: mean over 2 minutes) might be different, tcpO2-changes over time and the minimal value of the decrease from rest of oxygen pressure (DROPmin) results at exercise shall be concordant between the two systems. Patients and methods: Forty seven patients with arterial claudication (65 + / - 7 years) performed a treadmill test with 5 probes each of the electro-chemical and photo-optical devices simultaneously, one of each system on the chest, on each buttock and on each calf. Results: Seventeen Medicap® probes disconnected during the tests. tcpO2rest and DROPmin values were higher with Medicap® than with Radiometer®, by 13.7 + / - 17.1 mm Hg and 3.4 + / - 11.7 mm Hg, respectively. Despite the differences in absolute starting values, changes over time were similar between the two systems. The concordance between the two systems was approximately 70 % for classification of test results from DROPmin. Conclusions: Photo-optical sensors are promising alternatives to electro-chemical sensors for exercise oximetry, provided that miniaturisation and weight reduction of the new sensors are possible.

Neuropsychological Symptoms in Posttraumatic Stress Disorder and Changes Over Time

2007 ◽  
Author(s):  
Miranda Olff ◽  
Mirjam Nijdam ◽  
Kristin Samuelson ◽  
Julia Golier ◽  
Mariel Meewisse ◽  
...  
Keyword(s):  
Posttraumatic Stress Disorder ◽  
Posttraumatic Stress ◽  
Stress Disorder ◽  
Neuropsychological Symptoms ◽  
Changes Over Time ◽  
Over Time

Changes Over Time in Adaptive Behavior Functioning of Twice-Exceptional Children

2010 ◽  
Author(s):  
Rebecca D. Stinson ◽  
Zachary Sussman ◽  
Megan Foley Nicpon ◽  
Allison L. Allmon ◽  
Courtney Cornick ◽  
...  
Keyword(s):  
Adaptive Behavior ◽  
Exceptional Children ◽  
Twice Exceptional ◽  
Changes Over Time ◽  
Over Time
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