Effects of salinity and temperature on the performance of Cymodocea nodosa and Ruppia cirrhosa: a medium-term laboratory study

2019 ◽  
Vol 62 (2) ◽  
pp. 97-108
Author(s):  
Soultana Tsioli ◽  
Sotiris Orfanidis ◽  
Vasillis Papathanasiou ◽  
Christos Katsaros ◽  
Athanasios Exadactylos
Keyword(s):  
Thermal Tolerance ◽  
Coastal Lagoons ◽  
Future Climate Change ◽  
Effective Quantum Yield ◽  
Cymodocea Nodosa ◽  
Medium Term ◽  
Leaf Chlorophyll ◽  
Ruppia Cirrhosa ◽  
Growth Optimum ◽  
Different Temperatures

Abstract The effects of salinity and temperature on the photosynthetic and growth performance of the seagrasses Cymodocea nodosa and Ruppia cirrhosa were studied to understand their local seasonality and distribution. Cymodocea nodosa shoots were collected from Cape Vrasidas, and R. cirrhosa shoots from the coastal lagoon Fanari, all from the Eastern Macedonian and Thrace Region, Greece. Effective quantum yield (ΔF/Fm′), leaf chlorophyll-a content (mg g−1 wet mass) and growth (% of maximum) were tested at different temperatures (10–40°C) and salinities (5–60). The results showed that: (a) R. cirrhosa was more euryhaline (5–55/60) than C. nodosa (10–50), (b) the upper thermal tolerance of C. nodosa (34–35°C) was higher than that of R. cirrhosa (32–34°C), (c) C. nodosa could not tolerate 10°C, whereas R. cirrhosa could, and (d) the growth optimum of C. nodosa was 30°C and that of R. cirrhosa 20–30°C. The thermal optima and tolerances of growth and photosynthesis confirm the seasonal patterns of R. cirrhosa but not of C. nodosa. However, the sensitivity of C. nodosa to low salinities and temperatures may explain its absence from shallow coastal lagoons. Ruppia cirrhosa could be vulnerable to future climate change.

A temperate pollinator with high thermal tolerance is still susceptible to heat events predicted under future climate change

2018 ◽  
Vol 43 (4) ◽  
pp. 506-512 ◽  
Author(s):  
Timothy L. Sutton ◽  
Jane L. DeGabriel ◽  
Markus Riegler ◽  
James M. Cook
Keyword(s):  
Climate Change ◽  
Thermal Tolerance ◽  
Future Climate ◽  
Future Climate Change ◽  
Heat Events

Thermal tolerance and oxygen consumption rates of the catfish Horabagrus brachysoma (Günther) acclimated to different temperatures

Aquaculture ◽  
2009 ◽  
Vol 295 (1-2) ◽  
pp. 116-119 ◽  
Author(s):  
Rishikesh S. Dalvi ◽  
Asim K. Pal ◽  
Lalchand R. Tiwari ◽  
Tilak Das ◽  
Kartik Baruah
Keyword(s):  
Oxygen Consumption ◽  
Thermal Tolerance ◽  
Consumption Rates ◽  
Different Temperatures

Temperature optima for growth and photosynthetic processes in Trebouxia erici isolated from an Antarctic lichen and cultivated in a temperature gradient

2017 ◽  
Vol 7 (1) ◽  
pp. 34-44 ◽  
Author(s):  
Timm Bayer ◽  
Nıevas Vıals Alba
Keyword(s):  
Chlorophyll Fluorescence ◽  
Natural Populations ◽  
Effective Quantum Yield ◽  
Ps Ii ◽  
Chlorophyll Fluorescence Parameters ◽  
Different Temperatures ◽  
Chlorophyll Production ◽  
Time Courses ◽  
Temperature Optima

The temperature optimum for photosynthesis and growth of natural populations of Trebouxia erici isolated from an Antarctic lichen (Usnea antarctica) was determined using a long-term cultivation (26 days) at different temperatures. Several chlorophyll fluorescence parameters were used in T. erici cultivated in a liquid medium to assess the effect of cultivation temperature (0, 10, 20 and 30oC). Analysis of time courses of the capacity of photosynthetic processes in PS II (FV/FM), effective quantum yield of photosystem II (FPSII), relative fluorescence decline ratio (RFd), and quenching of background chlorophyll fluorescence (qF0) revealed that optimum temperature is between 10 to 20°C. Biomass production evaluated as a total chlorophyll production after 26 days of cultivation was maximal at 20°C. The results are discussed in relation to the data reported by other literature sources for Trebouxia sp. and other algae isolated from chlorolichens.

A Unifying Model to Estimate Thermal Tolerance Limits in Ectotherms Across Static, Dynamic and Fluctuating Exposures to Thermal Stress

2021 ◽  
Author(s):  
Lisa Bjerregaard Jørgensen ◽  
Hans Malte ◽  
Michael Ørsted ◽  
Nikolaj Andreasen Klahn ◽  
Johannes Overgaard
Keyword(s):  
Thermal Stress ◽  
Thermal Tolerance ◽  
Input Data ◽  
Thermal Injury ◽  
Accumulation Rate ◽  
Temperature Tolerance ◽  
Separate Experiment ◽  
Tolerance Limits ◽  
Dynamic Experiments ◽  
Different Temperatures

Abstract Temperature tolerance is critical for defining the fundamental niche of ectotherms and researchers classically use either static (exposure to a constant temperature) or dynamic (ramping temperature) assays to assess tolerance. The use of different methods complicates comparison between studies and here we present mathematical model (and R-scripts) to reconcile thermal tolerance measures obtained from static and dynamic assays. Our model uses input data from several static or dynamic experiments and is based on the well-supported assumption that thermal injury accumulation rate increases exponentially with temperature (recently re-introduced as Thermal Tolerance Landscapes). The model also assumes thermal stress at different temperatures to be additive and using experiments with Drosophila melanogaster, we validate these central assumptions by demonstrating that heat injury attained at different heat stress intensities and durations is additive. In a separate experiment we demonstrate that our model can accurately describe injury accumulation during fluctuating temperature stress and further we validate the model by successfully converting literature data of ectotherm heat tolerance (both static and dynamic assays) to a single, comparable metric (the temperature tolerated for 1 hour). The model presented here has many promising applications for the analysis of ectotherm thermal tolerance and we also discuss potential pitfalls that should be considered and avoided using this model.

scholarly journals Unshelled abalone and corrupted urchins: development of marine calcifiers in a changing ocean

2010 ◽  
Vol 278 (1716) ◽  
pp. 2376-2383 ◽  
Author(s):  
Maria Byrne ◽  
Melanie Ho ◽  
Eunice Wong ◽  
Natalie A. Soars ◽  
Paulina Selvakumaraswamy ◽  
...  
Keyword(s):  
Climate Change ◽  
Thermal Tolerance ◽  
Interactive Effect ◽  
Marine Species ◽  
Low Ph ◽  
Interactive Effects ◽  
Future Climate Change ◽  
Negative Effects ◽  
Negative Effect ◽  
Near Future

The most fragile skeletons produced by benthic marine calcifiers are those that larvae and juveniles make to support their bodies. Ocean warming, acidification, decreased carbonate saturation and their interactive effects are likely to impair skeletogenesis. Failure to produce skeleton in a changing ocean has negative implications for a diversity of marine species. We examined the interactive effects of warming and acidification on an abalone ( Haliotis coccoradiata ) and a sea urchin ( Heliocidaris erythrogramma ) reared from fertilization in temperature and pH/ p CO 2 treatments in a climatically and regionally relevant setting. Exposure of ectodermal (abalone) and mesodermal (echinoid) calcifying systems to warming (+2°C to 4°C) and acidification (pH 7.6–7.8) resulted in unshelled larvae and abnormal juveniles. Haliotis development was most sensitive with no interaction between stressors. For Heliocidaris , the percentage of normal juveniles decreased in response to both stressors, although a +2°C warming diminished the negative effect of low pH. The number of spines produced decreased with increasing acidification/ p CO 2 , and the interactive effect between stressors indicated that a +2°C warming reduced the negative effects of low pH. At +4°C, the developmental thermal tolerance was breached. Our results show that projected near-future climate change will have deleterious effects on development with differences in vulnerability in the two species.

scholarly journals A unifying model to estimate thermal tolerance limits in ectotherms across static, dynamic and fluctuating exposures to thermal stress

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lisa Bjerregaard Jørgensen ◽  
Hans Malte ◽  
Michael Ørsted ◽  
Nikolaj Andreasen Klahn ◽  
Johannes Overgaard
Keyword(s):  
Thermal Stress ◽  
Thermal Tolerance ◽  
Accumulation Rate ◽  
Temperature Tolerance ◽  
Separate Experiment ◽  
Time Curve ◽  
Death Time ◽  
Dynamic Experiments ◽  
Different Temperatures ◽  
Thermal Death Time

AbstractTemperature tolerance is critical for defining the fundamental niche of ectotherms and researchers classically use either static (exposure to a constant temperature) or dynamic (ramping temperature) assays to assess tolerance. The use of different methods complicates comparison between studies and here we present a mathematical model (and R-scripts) to reconcile thermal tolerance measures obtained from static and dynamic assays. Our model uses input data from several static or dynamic experiments and is based on the well-supported assumption that thermal injury accumulation rate increases exponentially with temperature (known as a thermal death time curve). The model also assumes thermal stress at different temperatures to be additive and using experiments with Drosophila melanogaster, we validate these central assumptions by demonstrating that heat injury attained at different heat stress intensities and durations is additive. In a separate experiment we demonstrate that our model can accurately describe injury accumulation during fluctuating temperature stress and further we validate the model by successfully converting literature data of ectotherm heat tolerance (both static and dynamic assays) to a single, comparable metric (the temperature tolerated for 1 h). The model presented here has many promising applications for the analysis of ectotherm thermal tolerance and we also discuss potential pitfalls that should be considered and avoided using this model.

scholarly journals Heatwave Effects on the Photosynthesis and Antioxidant Activity of the Seagrass Cymodocea nodosa under Contrasting Light Regimes

Oceans ◽  
2021 ◽  
Vol 2 (3) ◽  
pp. 448-460
Author(s):  
Monya M. Costa ◽  
João Silva ◽  
Isabel Barrote ◽  
Rui Santos
Keyword(s):  
Climate Change ◽  
Photosynthetic Pigments ◽  
Soluble Sugar ◽  
Soluble Sugars ◽  
Photochemical Efficiency ◽  
Climate Change Scenarios ◽  
Effective Quantum Yield ◽  
Cymodocea Nodosa ◽  
Antioxidant Responses ◽  
Ria Formosa

Global climate change, specifically the intensification of marine heatwaves, affect seagrasses. In the Ria Formosa, saturating light intensities may aggravate heatwave effects on seagrasses, particularly during low spring tides. However, the photophysiological and antioxidant responses of seagrasses to such extreme events are poorly known. Here, we evaluated the responses of Cymodocea nodosa exposed at 20 °C and 40 °C and 150 and 450 μmol quanta m−2 s−1. After four-days, we analyzed (a) photosynthetic responses to irradiance, maximum photochemical efficiency (Fv/Fm), the effective quantum yield of photosystem II (ɸPSII); (b) soluble sugars and starch; (c) photosynthetic pigments; (d) antioxidant responses (ascorbate peroxidase, APX; oxygen radical absorbance capacity, ORAC, and antioxidant capacity, TEAC); (d) oxidative damage (malondialdehyde, MDA). After four days at 40 °C, C. nodosa showed relevant changes in photosynthetic pigments, independent of light intensity. Increased TEAC and APX indicated an “investment” in the control of reactive oxygen species levels. Dark respiration and starch concentration increased, but soluble sugar concentrations were not affected, suggesting higher CO2 assimilation. Our results show that C. nodosa adjusts its photophysiological processes to successfully handle thermal stress, even under saturating light, and draws a promising perspective for C. nodosa resilience under climate change scenarios.

scholarly journals Rapid-warming tolerance correlates with tolerance to slow warming but not growth at non-optimal temperatures in zebrafish

2020 ◽  
Author(s):  
Eirik Ryvoll Åsheim ◽  
Anna H Andreassen ◽  
Rachael Morgan ◽  
Fredrik Jutfelt
Keyword(s):  
Global Warming ◽  
Thermal Stress ◽  
Growth Performance ◽  
Danio Rerio ◽  
Thermal Tolerance ◽  
Optimal Temperature ◽  
Medium Term ◽  
Physiological Mechanisms

Global warming is predicted to increase both acute and prolonged thermal challenges for aquatic ectotherms. Severe short and medium-term thermal stress over hours to days may cause mortality, while longer sub-lethal thermal challenges may cause performance declines. The interrelationship between the responses to short, medium and longer thermal challenges is unresolved. We asked if the same individuals are tolerant to both rapid and slow warming challenges, a question which has so far received little attention. Additionally, we investigated the possibility of a thermal syndrome where individuals in a population are distributed along a warm-type to cold-type axis. We tested whether different thermal traits correlate across individuals by acclimating 200 juvenile zebrafish (Danio rerio) to sub- or supra- optimal temperatures for growth (22 and 34°C) for 40 days and measured growth and thermal tolerance at two different warming rates. We found that tolerance to rapid warming correlated with tolerance to slow warming. However, individual tolerance to neither rapid nor slow warming correlated with growth at the supra-optimal temperature. We thus find some support for a syndrome-like organisation of thermal traits, but the lack of connection between tolerance and growth-performance indicates a restricted generality of a thermal syndrome. The results suggest that tolerance to rapid warming may share underlying physiological mechanisms with tolerance to slower heating, and indicate that the relevance of acute critical thermal tolerance extends beyond the rapid ramping rates used to measure them.

A Climate Policy for the Short and Medium Term: Stabilization or Adaptation?

2005 ◽  
Vol 16 (3-4) ◽  
pp. 667-680 ◽  
Author(s):  
Indur M. Goklany
Keyword(s):  
Climate Change ◽  
Climate Policy ◽  
Coastal Wetlands ◽  
Water Shortage ◽  
Future Climate Change ◽  
Medium Term ◽  
Global Impacts ◽  
Mitigate Climate Change ◽  
The Universe ◽  
Impacts Of Climate Change

An evaluation of analyses sponsored by the predecessor to the U.K. Department for Environment, Food and Rural Affairs (DEFRA) of the global impacts of climate change under various mitigation scenarios (including CO2. stabilization at 550 and 750 ppm) coupled with an examination of the relative costs associated with different schemes to either mitigate climate change or reduce vulnerability to various climate-sensitive hazards (namely, malaria, hunger, water shortage, coastal flooding, and losses of global forests and coastal wetlands) indicates that, at least for the next few decades, risks and/or threats associated with these hazards would be lowered much more effectively and economically by reducing current and future vulnerability to those hazards rather than through stabilization. Accordingly, over the next few decades the focus of climate policy should be to: (a) broadly advance sustainable development (particularly in developing countries since that would generally enhance their adaptive capacity to cope with numerous problems that currently beset them, including climate-sensitive problems), (b) reduce vulnerabilities to climate-sensitive problems that are urgent today and might be exacerbated by future climate change, and (c) implement “no-regret” emission reduction measures while at the same time striving to expand the universe of such measures through research and development of cleaner and more affordable technologies. Such a policy would help solve current urgent problems facing humanity while preparing it to face future problems that might be caused by climate change.

Sign in / Sign up

Export Citation Format

Share Document