| 1. |
- Kolzenburg, Regina
(författare)
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[future of blue carbon] Is pink the new blue?
- 2022
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Ingår i: Environment Coastal & Offshore Magazine. - : Technology Systems Corporation. - 2327-3445. ; :Special issue: Coastal blu carbon, s. 79-81
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- You don’t need to snorkel far offthe coast before you find large schools of fish and hear the sounds of snapping shrimp as the wavesbreak on the distant sandy beaches. If you stay in one spot for long enough it’s likely you will notice that you are actually surrounded by a huge amount of marine diversity as more fish come out of their hiding places along with a multitude of different crab species, sponges, starfish and brittle stars, sea cucumbers, clams and jellyfish. But this is no ordinary snorkelling tour on the tropical Great Barrier Reef or in the coral triangle; you are off the coast of Italy, England, or maybe even Iceland, and you are snorkelling across a bed of coralline algae.
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| 2. |
- Kolzenburg, Regina, et al.
(författare)
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Marginal populations show physiological adaptations and resilience to future climatic changes across a North Atlantic distribution
- 2021
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Ingår i: Environmental and Experimental Botany. - : Elsevier. - 0098-8472 .- 1873-7307. ; 188
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Tidskriftsartikel (refereegranskat)abstract
- Rising levels of anthropogenic carbon dioxide (CO2) in the atmosphere over the past several decades has resulted in a changing climate and is projected to further fuel global climate change in future centuries. Key components of climate change in the ocean are ocean acidification (decreasing pH and carbonate ion concentration [CO32-]) and rising sea surface temperatures. While several studies have investigated the effect of these climatic changes on a single population, very few studies have addressed effects on populations living at the margins of their species distribution and the full distributional range. This gap in knowledge impedes the determination of detailed predictions for most species’ futures. Over the course of four months, we investigated physiological changes (primary production, respiration, calcification and growth rates) of 6 populations of the intertidal ecosystem engineer and articulated coralline alga Corallina officinalis to future climatic conditions (low pH (∌7.8); T+3 °C; as well as the combination of low pH and T+3 °C). The populations (n = 2 per geographical location) represent the northern (Iceland) and southern (Spain) margins, as well as the centre (England) of the species distribution in the NE Atlantic. Here, we show that southern and central populations are already living closer to their thermal and stress limits, while Northern populations appear to be the most resilient to environmental changes. We present data confirming light calcification to be the most valuable physiological process which is prioritized in populations throughout the geographical gradient in the NE Atlantic. We found elevated temperature to have a greater effect on populations than pCO2. Investigating and monitoring organism physiology and structure under these extreme environmental conditions provides important information to predict their acclimatisation and resilience to future environmental conditions and potential changes in their distribution.
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| 3. |
- Kolzenburg, Regina, et al.
(författare)
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Photosynthetic response to a winter heatwave in leading andtrailing edge populations of the intertidal red alga Corallina officinalis (Rhodophyta)
- 2024
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Ingår i: Acta Oceanologica Sinica. - : Springer Nature. - 0253-505X .- 0253-4193.
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Tidskriftsartikel (refereegranskat)abstract
- Marine heatwaves (MHWs) caused by anthropogenic climate change are becoming a key driver of change at the ecosystem level. Thermal conditions experienced by marine organisms across their distribution, particularly towards the equator, are likely to approach their physiological limits, resulting in extensive mortality and subsequent changes at the population level. Populations at the margins of their species’ distribution are thought to be more sensitive to climate-induced environmental pressures than central populations, but our understanding of variability in fitness-related physiological traits in trailing versus leading-edge populations is limited. In a laboratory simulation study, we tested whether two leading (Iceland) and two trailing (Spain) peripheral populations of the intertidal macroalga Corallina officinalis display different levels of maximum potential quantum efficiency (Fv/Fm) resilience to current and future winter MHWs scenarios. Our study revealed that ongoing and future local winter MHWs will not negatively affect leading-edge populations of C. officinalis, which exhibited stable photosynthetic efficiency throughout the study. Trailing edge populations showed apositive though non-significant trend in photosynthetic efficiency throughout winter MHWs exposure. Poleward and equatorward populations did not produce significantly different results, with winter MHWs having no negative affect on Fv/Fm of either population. Additionally, we found no long-term regional or population-level influence of a winter MHWs on this species’ photosynthetic efficiency. Thus, we found no statistically significant difference in thermal stress responses between leading and trailing populations. Nonetheless, C. officinalis showed a trend towards higher stress responses in southern than northern populations. Because responses rest on a variety of local population traits, they are difficult to predict based solely on thermal pressures.
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| 4. |
- Kolzenburg, Regina, et al.
(författare)
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Physiological characterisation of the calcified alga Corallina officinalis (Rhodophyta) from the leading to trailing edge in the Northeast Atlantic
- 2023
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Ingår i: European journal of phycology. - : Taylor & Francis. - 0967-0262 .- 1469-4433. ; 58:1, s. 83-98
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Tidskriftsartikel (refereegranskat)abstract
- Intertidal macroalgae are exposed to many biotic and abiotic stressors, including significant fluctuations in environmental parameters such as salinity, temperature, pH and solar radiation. This study characterized populations of the intertidal calcifying red alga Corallina officinalis across its geographic distribution in the North-east Atlantic. Processes examined included primary production, respiration, light and dark calcification, photosynthesis-irradiance, and calcification-irradiance evolution. Results confirmed significant differences in the physiology of C. officinalis between latitudes with a clear north-to-south gradient. Compared with central and southern populations of this species, northern populations appeared to be the most robust, showing potential for local physiological adaptation in response to increased variability in environmental factors present within their habitat. Conversely, southern populations displayed a distinct lack of local adaptation compared with northern populations. This is possibly due to southern populations being located within an environment at the upper limit of their stress tolerance, therefore restricting the species’ ability to adapt. As a result, future permanent decline, or even disappearance, of C. officinalis within southern locations of the North-east Atlantic could occur, a process that is likely to be accelerated by predicted future climatic changes. Furthermore, given the essential role these ecosystem engineers play within their habitat, any loss of C. officinalis is also expected to have a strongly negative impact on the surrounding environment.
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| 5. |
- Kolzenburg, Regina, et al.
(författare)
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Structural integrity and skeletal trace elements in intertidal coralline algae across the Northeast Atlantic reveal a distinct separation of the leading and the trailing edge populations
- 2023
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Ingår i: Marine Environmental Research. - : Elsevier. - 0141-1136 .- 1879-0291. ; 190
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Tidskriftsartikel (refereegranskat)abstract
- Intertidal macroalgae, such as coralline algae, represent an essential structural element and substrate in rocky coastal zones. They have a high degree of flexibility allowing their survival in environments with severe mechanical stress during tidal cycles. This study characterised the genicula and intergenicula of the calcifying red algae Corallina officinalis across its geographic distribution in the Northeast Atlantic. Poleward populations have constructed more sturdy cell walls compared to equatorward populations, potentially due to greater local adaptations to higher frequency and intensity of environmental factors like storms and wave action. Southern populations showed a lack of local adaptation culminating in survival rather than thriving within their current environment, hence, they are located at the margin of this species' favourable conditions. Results clarify significant differences between latitudes and indicate a north-to-south gradient in this species’ skeletal elemental composition. Northern populations were dominated by cadmium, whereas chromium was the major trace element found in southern populations. In the future, these characteristics could lead to a permanent decline and a decrease in the ecosystem functions of C. officinalis in the southern locations in the Northeast Atlantic, which may be accelerated by predicted future climatic changes.
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| 6. |
- Kolzenburg, Regina
(författare)
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The direct influence of climate change on marginal populations : a review
- 2022
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Ingår i: Aquatic Sciences. - : Springer Nature. - 1015-1621 .- 1420-9055. ; 84:2
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Tidskriftsartikel (refereegranskat)abstract
- Climatic changes and their impact on animals and plants at the margins of their distributions are evident in terrestrial, limnic, and marine environments. I review and summarise the literature related to the direct physiological effects of climate change on marginal populations in all realms and categories. I summarise literature showing physiological and ecological emphasis but do not include studies on modelling, genetic or range shift. I found a great discrepancy in representation of each category, with the majority of studies and the greatest variety of species represented in the marine environment and the least research conducted in limnic environments. The least represented in all environments and marginalities was the plant kingdom, including algae. I identified an uneven distribution of studies around the globe with a major focus on Europe and North America. Literature results show an overarching negative impact on organismal physiology independent of a realm and/or geographic location, potentially leading to species and hence biodiversity loss, and tightly coupled with this, a loss of ecosystem functions at the respective sites. All these points may lead to unstable ecosystems and socio-economic implications at the respective sites.
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| 7. |
- Kolzenburg, Regina, et al.
(författare)
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Understanding the margin squeeze : differentiation in fitness-related traits between central and trailing edge populations of Corallina officinalis
- 2019
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Ingår i: Ecology and Evolution. - : John Wiley & Sons. - 2045-7758. ; 9:10, s. 5787-5801
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Tidskriftsartikel (refereegranskat)abstract
- Assessing population responses to climate-related environmental change is key to understanding the adaptive potential of the species as a whole. Coralline algae are critical components of marine shallow water ecosystems where they function as important ecosystem engineers. Populations of the calcifying algae Corallina officinalis from the center (southern UK) and periphery (northern Spain) of the North Atlantic species natural distribution were selected to test for functional differentiation in thermal stress response. Physiological measurements of calcification, photosynthesis, respiration, growth rates, oxygen, and calcification evolution curves were performed using closed cell respirometry methods. Species identity was genetically confirmed via DNA barcoding. Through a common garden approach, we identified distinct vulnerability to thermal stress of central and peripheral populations. Southern populations showed a decrease in photosynthetic rate under environmental conditions of central locations, and central populations showed a decline in calcification rates under southern conditions. This shows that the two processes of calcification and photosynthesis are not as tightly coupled as previously assumed. How the species as whole will react to future climatic changes will be determined by the interplay of local environmental conditions and these distinct population adaptive traits.
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| 8. |
- Ragazzola, Federica, et al.
(författare)
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An intertidal life : Combined effects of acidification and winter heatwaves on a coralline alga (Ellisolandia elongata) and its associated invertebrate community
- 2021
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Ingår i: Marine Environmental Research. - : Elsevier. - 0141-1136 .- 1879-0291. ; 169
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Tidskriftsartikel (refereegranskat)abstract
- In coastal marine ecosystems coralline algae often create biogenic reefs. These calcareous algal reefs affect their associated invertebrate communities via diurnal oscillations in photosynthesis, respiration and calcification processes. Little is known about how these biogenic reefs function and how they will be affected by climate change. We investigated the winter response of a Mediterranean intertidal biogenic reef, Ellissolandia elongata exposed in the laboratory to reduced pH conditions (i.e. ambient pH – 0.3, RCP 8.5) together with an extreme heatwave event (+1.4 °C for 15 days). Response variables considered both the algal physiology (calcification and photosynthetic rates) and community structure of the associated invertebrates (at taxonomic and functional level). The combination of a reduced pH with a heatwave event caused Ellisolandia elongata to significantly increase photosynthetic activity. The high variability of calcification that occurred during simulated night time conditions, indicates that there is not a simple, linear relationship between these two and may indicate that it will be resilient to future conditions of climate change.In contrast, the associated fauna were particularly negatively affected by the heatwave event, which impoverished the communities as opportunistic taxa became dominant. Local increases in oxygen and pH driven by the algae can buffer the microhabitat in the algal fronds, thus favouring the survival of small invertebrates.
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| 9. |
- Ragazzola, Federica, et al.
(författare)
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Carbonate chemistry and temperature dynamics in an alga dominated habitat
- 2021
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Ingår i: Regional Studies in Marine Science. - : Elsevier. - 2352-4855. ; 44
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Tidskriftsartikel (refereegranskat)abstract
- Recent works have begun to explore the magnitude and frequency of localized changes in seawater chemistry in shallow water systems, where the effects of warming and acidification are still unpredictable. In a Mediterranean shallow coastal site, we empirically characterized the diel, seasonal, and annual pattern of pH, temperature, and associated chemical changes on one Ellisolandia elongata ‘corniche’, (i.e. a coastal algal biogenic reef). Local benthic metabolism together with temperature, were two of the main drivers for the carbonate system variation over diel and seasonal cycles. During the 12-month study, a total of seven heatwave events were recorded (two of which occurred in winter) with the longest lasting 11 days. The present study highlights the importance of improving the knowledge of changes and dynamics occurring at local scale, by extending in situ data acquisition at shallow coastal sites, in order to better assess the impacts of climate change on both environment and ecosystems.
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| 10. |
- Ragazzola, Federica, et al.
(författare)
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Early stage ecological communities on artificial algae showed no difference in diversity and abundance under ocean acidification
- 2024
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Ingår i: Hydrobiologia. - : Springer Science+Business Media B.V.. - 0018-8158 .- 1573-5117. ; 851:8, s. 1939-1955
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Tidskriftsartikel (refereegranskat)abstract
- Marine habitat-forming species create structurally complex habitats that host macroinvertebrate communities characterized by remarkable abundance and species richness. These habitat-forming species also play a fundamental role in creating favourable environmental conditions that promote biodiversity. The deployment of artificial structures is becoming a common practice to help offset habitat loss although with mixed results. This study investigated the suitability of artificial flexible turfs mimicking the articulated coralline algae (mimics) as habitat providers and the effect of ocean acidification (OA) on early stage ecological communities associated to flexible mimics and with the mature community associated to Ellisolandia elongata natural turfs. The mimics proved to be a suitable habitat for early stage communities. During the OA mesocosms experiment, the two substrates have been treated and analysed separately due to the difference between the two communities. For early stage ecological communities associated with the mimics, the lack of a biologically active substrate does not exacerbate the effect of OA. In fact, no significant differences were found between treatments in crustaceans, molluscs and polychaetes diversity and abundance associated with the mimics. In mature communities associated with natural turfs, buffering capability of E. elongata is supporting different taxonomic groups, except for molluscs, greatly susceptible to OA.
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