VTMaxHerp : a data set of Voluntary Thermal Maximum temperatures of amphibians and reptiles from two Brazilian hotspots

The Paleocene-Eocene Thermal Maximum (PETM; ca. 55.8 Ma) is thought to coincide with a profound but entirely transient change among nannoplankton communities throughout the ocean. Here we explore the ecology of nannoplankton during the PETM by using multivariate analyses of a global data set that is based upon the distribution of taxa in time and space. We use these results, coupled with stable isotope data and geochemical modeling, to reinterpret the ecology of key genera. The results of the multivariate analyses suggest that the community was perturbed significantly in coastal and high-latitudes sites compared to the open ocean, and the relative influence of temperature and nutrient availability on the assemblage varies regionally. The open ocean became more stratified and less productive during the PETM and the oligotrophic assemblage responded primarily to changes in nutrient availability. Alternatively, assemblages at the equator and in the Southern Ocean responded to temperature more than to nutrient reduction. In addition, the assemblage change at the PETM was not merely transient—there is evidence of adaptation and a long-term change in the nannoplankton community that persists after the PETM and results in the disappearance of a high-latitude assemblage. The long-term effect on communities caused by transient warming during the PETM has implications for modern-day climate change, suggesting similar permanent changes to nannoplankton community structure as the oceans warm.

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Critical Thermal Maximum Temperatures in Australian Scincid Lizards: Their Ecological and Evolutionary Significance.

Australian Journal of Zoology ◽

10.1071/zo9800091 ◽

1980 ◽

Vol 28 (1) ◽

pp. 91 ◽

Cited By ~ 25

Author(s):

AE Greer

Keyword(s):

Maximum Temperature ◽

Evolutionary Significance ◽

Thermal Barrier ◽

Critical Thermal Maximum ◽

Thermal Maximum ◽

Surface Dwelling ◽

Maximum Temperatures

The critical thermal maximum temperature (CTMAX) has now been determined for representatives of 16 of the 21 genera of scincid lizards in Australia. Taxa from the warm interior of the country generally have a mean CTMAX greater than 39.5�C regardless of their behaviour or habitat. Taxa from the cooler periphery of the continent fall into two groups based on their behaviour and habitat: diurnal, surface- dwelling forms generally have a mean CTMAX above 39.5�C whereas crepuscular to nocturnal. or cryptozoic to fossorial forms, have a mean CTMAX below 39.5�C. The skinks of the interior probably evolved from ancestors occupying habitats most similar to ones now occurring on the periphery. In these more equable habitats. diurnal surface-dwelling forms, with their high CTMAX, would have been preadapted to invade the habitats of the interior, whereas crepuscular to nocturnal. or cryptozoic to fossorial forms, with their low CTMAX, may have had to overcome a thermal barrier to enter these habitats. This may account in part for the paucity of crepuscular to nocturnal or cryptozoic to fossorial skink lineages in the interior. Unlike most other lizard families, most skinks do not pant when heat stressed. The reasons for this are unknown.

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Recent trends in the climate of Namaqualand, a megadiverse arid region of South Africa

South African Journal of Science ◽

10.17159/sajs.2016/20150217 ◽

2016 ◽

Vol Volume 112 (Number 3/4) ◽

Cited By ~ 9

Author(s):

Claire L. Davis ◽

M. Timm Hoffman ◽

Wesley Roberts ◽

◽

...

Keyword(s):

Climate Change ◽

Climate Change Impacts ◽

Future Climate Change ◽

Data Set ◽

Rainfall Events ◽

Reliable Assessment ◽

Coastal Fog ◽

Recent Trends ◽

Weather Stations ◽

Maximum Temperatures

Abstract Namaqualand is especially vulnerable to future climate change impacts. Using a high-resolution (0.5°x0.5°) gridded data set (CRU TS 3.1) and individual weather station data, we demonstrated that temperatures as well as frequency of hot extremes have increased across this region. Specifically, minimum temperatures have increased by 1.4 °C and maximum temperatures by 1.1 °C over the last century. Of the five weather stations analysed, two showed evidence of a significant increase in the duration of warm spells of up to 5 days per decade and a reduction in the number of cool days (TX10P) by up to 3 days per decade. In terms of rainfall, we found no clear evidence for a significant change in annual totals or the frequency or intensity of rainfall events. Seasonal trends in rainfall did, however, demonstrate some spatial variability across the region. Spatial trends in evapotranspiration obtained from the 8-day MOD16 ET product were characterised by a steepening inland-coastal gradient where areas along the coastline showed a significant increase in evapotranspiration of up to 30 mm per decade, most notably in spring and summer. The increase in temperature linked with the increases in evapotranspiration pose significant challenges for water availability in the region, but further research into changes in coastal fog is required in order for a more reliable assessment to be made. Overall, the results presented in this study provide evidence-based information for the management of climate change impacts as well as the development of appropriate adaptation responses at a local scale.

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Reconstruction of early Holocene Thermal Maximum temperatures using present vertical distribution of conifers in the Pannon region (SE Central Europe)

The Holocene ◽

10.1177/0959683616658528 ◽

2016 ◽

Vol 27 (2) ◽

pp. 236-245 ◽

Cited By ~ 3

Author(s):

Attila Molnár ◽

Zsolt Végvári

Keyword(s):

Early Holocene ◽

Mean Annual Temperature ◽

Main Subject ◽

Sensitive Species ◽

General Sense ◽

Holocene Thermal Maximum ◽

The North ◽

Thermal Maximum ◽

The Mean ◽

Maximum Temperatures

Palaeoclimatic reconstruction is a main subject of palaeoecology, clarifying fossil palaeoenvironmental patterns. Our study provides a macroecological approach to reconstruct the mean annual temperature (MAT) of the Pannon region at the early Holocene Thermal Maximum (HTM, warmest period of the Holocene), based on the absence of forest-dwelling conifers in the North Hungarian Mountains and their presence in the surrounding Carpathians on the same altitude. We suppose that the HTM was enough warm to drive conifers to extinction from elevations between 900 and 1100 m a.s.l. in the relatively isolated N-Hungarian Mts. Conversely, HTM still allowed the survival of residual dwarf pine ( Pinus mugo) stands on the isolated peaks of the West Transylvanian Mountains between 1600 and 1800 m a.s.l. Our study provides an estimate for the value of MAT of HTM of Pannon region with an interval of 0.4°C, relying on macroecological considerations. We calculate the temperature of the HTM 1.3–1.7°C warmer than the present temperature. This method can be used in a general sense, if conditions meet the requirements of the method even in horizontal cases, with area isolates of climate-sensitive species.

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First Report of Foliar Infection of Cabbage by Phytophthora drechsleri in Argentina

Plant Disease ◽

10.1094/pdis-04-12-0342-pdn ◽

2012 ◽

Vol 96 (12) ◽

pp. 1830-1830

Author(s):

M. J. Iribarren ◽

B. A. González ◽

M. L. Velez ◽

A. Greslebin ◽

M. Steciow

Keyword(s):

Buenos Aires ◽

Tap Water ◽

Its Region ◽

Buenos Aires Province ◽

Data Set ◽

First Report ◽

Morphological Studies ◽

Mycelial Plug ◽

Phytophthora Drechsleri ◽

Maximum Temperatures

Cabbage (Brassica oleracea var. capitata L.) is a popular crop grown along the northeast horticultural belt of Buenos Aires Province, Argentina. In the summer of 2010, fields in this region remained flooded for long periods due to frequent and intense precipitation (560 mm from January to March). Commercial cabbage crops in the cities of Luján and General Rodríguez developed patches of diseased plants that were stunted and wilted. Affected plants had necrotic areas in the crowns and roots. Symptoms expanded to the upper stems, leaving vascular tissues exposed. During April 2010, samples from 2 fields were brought to the laboratory where the stems were washed thoroughly and disinfected with a 1% bleach solution for 2 minutes. Small pieces (5 mm in diameter) were removed from the lesion edge, plated on V8 agar (V8A) plates, and incubated at 24°C in the dark for 5 days. Four isolates were transferred to V8A using hyphal tips. Morphological studies were performed on the V8A cultures as well as plates flooded with tap water. Sporangia were obpyriform, nonpapillate, persistent, and variable in size, averaging 44 × 28 μm. Each isolate belonged to the A1 mating type when paired with P. capsici tester isolates, CBS 370.72 and CBS 111.334 (Fungal Biodiversity Centre, CBS, Utrecht, the Netherlands). The isolates produced amphigynous antheridia, and chlamydospores were present but scarce. Maximum temperatures for growth (37°C) were also performed. Edited sequences of the internal transcribed spacer (ITS) region of the rDNA (GenBank Accession Nos. JQ653300, JQ653301, JQ653302, and JQ653303) were compared with Phytophthora sequences available in GenBank using the BLASTN search utility (1) and aligned to the data set of Cooke et al. (2). Sequences of the four isolates (strains 2: R-cai-cuello-col-3, 3: R-cai-cuello-col-18, 4: R-AN-col-1A and 5: R-AN-col-1B) matched 100% with GenBank sequences of P. drechsleri (100% coverage, 100% identity and no gaps). Based on these results, the four Argentinian cabbage isolates were identified as P. drechsleri (3). Pathogenicity tests were completed using three detached heads of mature cabbage plants (B. oleracea var. capitata) for each isolate. A 5-mm colonized mycelial plug of the appropriate isolate was placed on the main vein of the outermost leaves. For the control treatments, three heads were inoculated with non-colonized V8A plugs. The inoculated and control heads of cabbage were incubated in plastic boxes wrapped in black nylon bags at 24°C for 4 days. Broccoli (B. oleracea var. italica) and cauliflower (B. oleracea var. botrytis) were also tested following the same procedure. All heads of cabbage, broccoli, and cauliflower developed necrotic lesions 2 to 4 cm in diameter and a dark grey color. Control heads of each plant remained green. P. dreschleri was consistently reisolated as described above from the inoculated heads, but not from the control heads. To our knowledge, this is the first report of cabbage as a host for P. dreschleri in Argentina. Frezzi (4) reported this species as a pathogen of Chrysanthemum cinerariefolium, Celosia plumosa, Schinus molle, and Solanum lycopersicum in Argentina in 1950. References: (1) S. S. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) D. E. L. Cooke et al. Fungal Gen. Biol. 30:17, 2000. (3) D. C. Erwin and O. K. Ribeiro. Phytophthora Diseases Worldwide. The American Phytopathological Society Press, St. Paul, MN, 1996. (4) M. J. Frezzi. Rev. Invest. Agric. Buenos Aires 4:49, 1950.

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Last interglacial model–data mismatch of thermal maximum temperatures partially explained

Climate of the Past ◽

10.5194/cp-10-1633-2014 ◽

2014 ◽

Vol 10 (4) ◽

pp. 1633-1644 ◽

Cited By ~ 13

Author(s):

P. Bakker ◽

H. Renssen

Keyword(s):

Climate Models ◽

Temporal Variations ◽

Model Data ◽

Last Interglacial ◽

Underlying Assumption ◽

Thermal Maximum ◽

Spatio Temporal ◽

Maximum Temperatures ◽

The Impact ◽

Global Mean

Abstract. The timing of the last interglacial (LIG) thermal maximum across the globe remains to be precisely assessed. Because of difficulties in establishing a common temporal framework between records from different palaeoclimatic archives retrieved from various places around the globe, it has not yet been possible to reconstruct spatio-temporal variations in the occurrence of the maximum warmth across the globe. Instead, snapshot reconstructions of warmest LIG conditions have been presented, which have an underlying assumption that maximum warmth occurred synchronously everywhere. Although known to be an oversimplification, the impact of this assumption on temperature estimates has yet to be assessed. We use the LIG temperature evolutions simulated by nine different climate models to investigate whether the assumption of synchronicity results in a sizeable overestimation of the LIG thermal maximum. We find that for annual temperatures, the overestimation is small, strongly model-dependent (global mean 0.4 ± 0.3 °C) and cannot explain the recently published 0.67 °C difference between simulated and reconstructed annual mean temperatures during the LIG thermal maximum. However, if one takes into consideration that temperature proxies are possibly biased towards summer, the overestimation of the LIG thermal maximum based on warmest month temperatures is non-negligible with a global mean of 1.1 ± 0.4 °C.

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Optimum and maximum temperatures of sockeye salmon (Oncorhynchus nerka) populations hatched at different temperatures

Canadian Journal of Zoology ◽

10.1139/cjz-2012-0300 ◽

2013 ◽

Vol 91 (5) ◽

pp. 265-274 ◽

Cited By ~ 35

Author(s):

Z. Chen ◽

K. Anttila ◽

J. Wu ◽

C.K. Whitney ◽

S.G. Hinch ◽

...

Keyword(s):

Heart Rate ◽

Sockeye Salmon ◽

Incubation Temperature ◽

Oncorhynchus Nerka ◽

Temperature Tolerance ◽

Development Stage ◽

Thermal Maximum ◽

Different Temperatures ◽

Maximum Temperatures ◽

The Relationship

Temperature tolerance and heart rates were compared among nine sockeye salmon (Oncorhynchus nerka (Walbaum in Artedi, 1792)) populations, whose eggs were incubated at 10, 14, and 16 °C before rearing all hatchlings at a common temperature. Critical thermal maximum (CTmax) significantly differed among populations and temperature treatments. Populations with shorter migration distance and a lower migration and spawning temperature tended to have higher CTmax at 90 days posthatch. However, the relationship was reversed when fish of similar size were compared at 135–214 days posthatch. CTmax at 90 days posthatch was also positively related to body mass, which differed appreciably among populations at this development stage. With growth, the population differences in CTmax diminished from 3.1 to 1 °C. Elevated incubation temperature also decreased CTmax. Arrhenius breakpoint temperature (ABT) for maximum heart rate differed among populations incubated at 14 °C. The Chilko Lake population, which rear at 1.2 km above sea level, had the highest heart rate across all temperatures when incubated at 14 °C, but the lowest ABT among populations. This study provides clear evidence for the local adaptation among sockeye salmon populations with respect to temperature tolerance and cardiac capacity, information that adds to the debate on whether intraspecific variance is adaptive, or a constraint, or both.

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Predicting Yield and Time to Maturity of Muskmelons from Weather and Crop Observations

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.123.2.195 ◽

1998 ◽

Vol 123 (2) ◽

pp. 195-201 ◽

Cited By ~ 4

Author(s):

Sylvie Jenni ◽

Katrine A. Stewart ◽

Gaétan Bourgeois ◽

Daniel C. Cloutier

Keyword(s):

Total Yield ◽

Developmental Time ◽

Daily Maximum ◽

Base Temperature ◽

Heat Unit ◽

Data Set ◽

Simple Method ◽

Fruit Maturity ◽

Richards Function ◽

Maximum Temperatures

A simple method to predict time from anthesis of perfect flowers to fruit maturity (full slip) and yield is presented here for muskmelon (Cucumis melo L.) grown in a northern climate. Developmental time for individual muskmelons from anthesis to full slip could be predicted from several heat unit formulas, depending on the temperature data set used. When temperature at 7.5 cm above soil level was used, the heat unit formula resulting in the lowest coefficient of variation (cv=6.9%) accumulated daily average temperatures with a base temperature of 11 °C and an upper threshold of 25 °C. With temperatures recorded at a meteorological station located 2 km from the experimental field, the method showing the lowest cv (8.9%) accumulated daily maximum temperatures with a base temperature of 15 °C. This latter method was improved by including a 60-degree-day lag for second cycle fruit. The proportion of fruit volume at full slip of 22 fruit from the first cycle could be described by a common Richards function (R2=0.99). Although 65% of the plants produced two fruit cycles, fruit from the first cycle represented 72% of total yield in terms of number and mass. The blooming period of productive flowers lasted 34 days, each cycle overlapping and covering an equal period of 19 days. Counting the number of developing fruit >4 cm after 225 degree days from the start of anthesis (when 90% of the plants have at least one blooming perfect flower) could rapidly estimate the number of fruit that will reach maturity.

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Yield of Müller-Thurgau and Riesling grapevines is altered by meteorological conditions in the current and previous growing seasons

OENO One ◽

10.20870/oeno-one.2016.50.4.1071 ◽

2017 ◽

Vol 50 (4) ◽

Author(s):

Markus Keller ◽

Daniel Molitor

Keyword(s):

Meteorological Data ◽

Early Spring ◽

Meteorological Conditions ◽

Data Set ◽

Growing Seasons ◽

Winter Temperatures ◽

Maximum Temperatures ◽

Interannual Fluctuations ◽

Yield Formation ◽

The Impact

Background and Aims:Grape yields show distinct interannual fluctuations caused by environmental conditions. Statistical investigations based on a 22-year data set (1993-2015) of annual yields of two grape cultivars grown in Luxembourg aimed at (i) investigating the impact of meteorological conditions during specific phases of yield formation, (ii) identifying meteorological conditions with predictive value for annual grape yield, and (iii) developing models to simulate yield based on meteorological data.Methods and Results:Window pane analysis showed that pre-bloom and bloom minimum temperatures and precipitation sums in the preceding year, winter temperatures, spring temperatures, and post-veraison minimum temperatures in the current year were positively correlated with annual yield; early spring and post-harvest temperatures in the preceding year, and, for Riesling, pre-bloom precipitation sums and post-bloom maximum temperatures in the current year were negatively correlated with annual yield. Models developed from these data simulated annual yield with high accuracy (R2adj = 0.88 for Riesling, and R2adj = 0.92 for Müller-Thurgau).Conclusions:Meteorological conditions during distinct periods of yield formation are correlated with annual yield. Yield models can be used in practical viticulture as well as in climate change impact studies.Significance of the study:Enhanced understanding of the effects of meteorological conditions during specific periods of yield formation supports growers’ efforts to optimize viticultural measures aimed at achieving adequate yield levels.

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Aridity and land use negatively influencea dominant species' upper critical thermal limits

PeerJ ◽

10.7717/peerj.6252 ◽

2019 ◽

Vol 6 ◽

pp. e6252 ◽

Cited By ~ 4

Author(s):

Nigel R. Andrew ◽

Cara Miller ◽

Graham Hall ◽

Zac Hemmings ◽

Ian Oliver

Keyword(s):

Land Use ◽

Environmental Gradients ◽

New South ◽

Landscape Fragmentation ◽

Thermal Limits ◽

South Wales ◽

Thermal Maximum ◽

Critical Thermal Limits ◽

Physiological Tolerances ◽

Maximum Temperatures

Understanding the physiological tolerances of ectotherms, such as thermal limits, is important in predicting biotic responses to climate change. However, it is even more important to examine these impacts alongside those from other landscape changes: such as the reduction of native vegetation cover, landscape fragmentation and changes in land use intensity (LUI). Here, we integrate the observed thermal limits of the dominant and ubiquitous meat antIridomyrmex purpureusacross climate (aridity), land cover and land use gradients spanning 270 km in length and 840 m in altitude across northern New South Wales, Australia. Meat ants were chosen for study as they are ecosystem engineers and changes in their populations may result in a cascade of changes in the populations of other species. When we assessed critical thermal maximum temperatures (CTmax) of meat ants in relation to the environmental gradients we found little influence of climate (aridity) but that CTmaxdecreased as LUI increased. We found no overall correlation between CTmaxand CTmin. We did however find that tolerance to warming was lower for ants sampled from more arid locations. Our findings suggest that as LUI and aridification increase, the physiological resilience ofI. purpureuswill decline. A reduction in physiological resilience may lead to a reduction in the ecosystem service provision that these populations provide throughout their distribution.

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