Increased Temperature Due to Global Warming Alters the Respiratory Potential in Aquatic Organisms from an Oligotrophic Lake

Heavy metal pollution in urban lakes of Hanoi has become one of the major environmental issues in the last decades. Research on the toxicity of Pb is necessary due to the extent of its harm to aquatic ecosystems. The toxicity of Pb to aquatic organisms (EC50 values) depends on different environmental conditions. The study was conducted to evaluate the effect of temperature on the toxicity of Pb on the test organism Moina Dubia. Moina Dubia belongs to the Cladocera group (Cladocera) which is an indigenous creature collected at Lake Hanoi. Moina Dubia was cultured under laboratory conditions and has been used to conduct EC50 determination for Pb. Moina Dubia grew and developed well in the laboratory and was suitable as a test organism in toxicological studies. A survey from 24oC to 28oC water temperature conditions showed that the EC50 value decreases from 1402 ug/l to 775 ug/l. The higher water temperature, the higher toxicity level of Pb on Moina Dubia. Clear impact of water temperature on toxicity of heavy metal as Pb showed that global warming may gradually lead to potential biodegradation in freshwater ecology.

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Ecophysiological responses of two closely related epigean and hypogean Niphargus species to hypoxia and increased temperature: Do they differ?

International Journal of Speleology ◽

10.5038/1827-806x.50.2.2369 ◽

2021 ◽

Vol 50 (2) ◽

pp. 111-120

Author(s):

Tatjana Simčič ◽

Boris Sket

Keyword(s):

Oxygen Consumption ◽

Antioxidant Activities ◽

Reductase Activity ◽

Aquatic Organisms ◽

Metabolic Potential ◽

Physiological And Biochemical Characteristics ◽

Increased Temperature ◽

Oxygen Conditions ◽

Glutathione Reductase Activity ◽

Physiological And Biochemical

Ecological performance of animals depends on physiological and biochemical processes that are adjusted to the environment. The responses to hypoxia or anoxia have been frequently studied in subterranean aquatic organisms in order to find potential adaptations to restrict oxygen conditions occurring in the underground habitats. However, some previous studies have compared phylogenetic distant epigean and hypogean species or the epigean and hypogean populations of the same species due to little chance to compare closely related epigean and hypogean species. Therefore, in this study, we compared the effects of exposure to hypoxia, followed by reoxygenation, and increased temperature on oxygen consumption, potential metabolic activity, and antioxidant activities in closely related epigean and hypogean species: Niphargus zagrebensis and N. stygius. Oxygen consumption of N. stygius increased similarly during post-hypoxic recovery at 10 and 20°C (approx. 5-times), while N. zagrebensis increased its oxygen consumption for 9.7 and 4.4-times at 10 and 20°C, respectively. We observed higher exploitation of metabolic potential for current oxygen consumption during reoxygenation in N. zagrebensis than N. stygius. Exposure to hypoxia and subsequent reoxygenation at 20°C increased catalase (CAT) activity in N. stygius, but not in N. zagrebensis. We observed increased glutathione reductase activity in both Niphargus species. We concluded that respiratory and antioxidant responses to severe hypoxia and increased temperature differed between closely related epigean and hypogean Niphargus species. Hypogean Niphargus species possess physiological and biochemical characteristics that are advantageous in temperature stable subterranean environments which support inhabiting of species that have low energetic demands, while epigean Niphargus species can successfully inhabit specific surface habitats.

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EFFECTS OF GLOBAL WARMING AND ANTHROPOGENIC FACTORS ON AQUATIC LIFE

Materials of XXVII International Coastal Conference "Arctic shores: shore-up to sustainability" ◽

10.31519/conferencearticle_5cebbc14abe349.69831818 ◽

2019 ◽

Author(s):

Yanik Telat ◽

Aslan Irfan ◽

Aslan Irfan

Keyword(s):

Global Warming ◽

Fish Species ◽

Climate Warming ◽

Food Industry ◽

Economic Impacts ◽

Aquatic Organisms ◽

Anthropogenic Factors ◽

Aquatic Life ◽

Factors Affecting ◽

Natural And Anthropogenic Factors

Based on the assumptions of many researchers, global warming and anthropogenic factors such as pollution, transporting and trading, as well as invasionism, lessepsianism, endangerism effect negatively and will continue to effect aquatic populations and their existence in the ecosystem and related habitats. Thus, it may be stated that climate warming and anthropogenic factors will certainly cause extinction of some aquatic organisms as well as fish species in the end, by 2080 or 2100. Considering economic impacts of losing some species, the new areas of fishing should be decided to sustain current needs of human and food industry. In this paper, the effects of global warming, natural and anthropogenic factors affecting aquatic life were discussed by using the data from various reports.

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Modelling ecosystem adaptation and dangerous rates of global warming

Emerging Topics in Life Sciences ◽

10.1042/etls20180113 ◽

2019 ◽

Vol 3 (2) ◽

pp. 221-231 ◽

Cited By ~ 4

Author(s):

Rebecca Millington ◽

Peter M. Cox ◽

Jonathan R. Moore ◽

Gabriel Yvon-Durocher

Keyword(s):

Climate Change ◽

Global Warming ◽

Diffusion Rate ◽

Individual Species ◽

Genetic Evolution ◽

Rates Of Change ◽

Rapid Climate Change ◽

Warming Climate ◽

Intraspecies Competition ◽

High Trait

Abstract We are in a period of relatively rapid climate change. This poses challenges for individual species and threatens the ecosystem services that humanity relies upon. Temperature is a key stressor. In a warming climate, individual organisms may be able to shift their thermal optima through phenotypic plasticity. However, such plasticity is unlikely to be sufficient over the coming centuries. Resilience to warming will also depend on how fast the distribution of traits that define a species can adapt through other methods, in particular through redistribution of the abundance of variants within the population and through genetic evolution. In this paper, we use a simple theoretical ‘trait diffusion’ model to explore how the resilience of a given species to climate change depends on the initial trait diversity (biodiversity), the trait diffusion rate (mutation rate), and the lifetime of the organism. We estimate theoretical dangerous rates of continuous global warming that would exceed the ability of a species to adapt through trait diffusion, and therefore lead to a collapse in the overall productivity of the species. As the rate of adaptation through intraspecies competition and genetic evolution decreases with species lifetime, we find critical rates of change that also depend fundamentally on lifetime. Dangerous rates of warming vary from 1°C per lifetime (at low trait diffusion rate) to 8°C per lifetime (at high trait diffusion rate). We conclude that rapid climate change is liable to favour short-lived organisms (e.g. microbes) rather than longer-lived organisms (e.g. trees).

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