| 1. |
- Ammar, Yosr, 1992-
(författare)
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Novelty in social-ecological systems: understanding the past to plan the future
- 2020
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Human activities are shaping the Earth system and creating novel properties in the intertwined Social-Ecological Systems (SES). Although novelty is acknowledged in SES theories, the concept of novelty is not well understood, and little mathematical formalization and empirical foundations have been made. Building on the theoretical frameworks of Complex Adaptive Systems (CAS) and concepts of novelty in ecology, this licentiate thesis suggests a first attempt to quantify novelty in a marine ecosystem, in a SES context. Here, I focus on the past emergence of novelty in a marine SES to better understand when and where novelty has emerged and which drivers affect this emergence. Novelty emerges in a CAS when it has moved beyond its historical range of variation. The historical state depends on the temporal and spatial scale as well as the context of the study. Building on the characteristics of CAS, novelty is multidimensional, emerges on a continuum, can be nonlinear, and follows baseline specific trajectories. It has been quantified as the degree of dissimilarity of a system relative to a specific baseline. I used the case of the Baltic Sea SES, where long-term data exists, and many ecological, political, and economic changes have been recorded. Here, I focus on structural changes of the system rather than interactions and feedbacks. Paper 1 focuses on the ecological novelty in the Baltic Sea and contributes as the first study that quantifies novelty in marine ecosystems and across different trophic levels. Results reveal that over the 35-year study-period (1980-2015), novelty has emerged following the pattern of change, but at a slower pace. It has emerged in complex temporal and spatial pattern of the tested abiotic and biotic components. Both abiotic and biotic novelty showed a higher rate of novelty in confined northern basins than in the Central Baltic Sea, which indicated that some areas are more susceptible to the rise of novelty than others. Temperature and salinity were identified as the main abiotic drivers of biotic novelty in the Baltic Sea. Paper 2 contributes as the first study to quantify socio-economic novelty in a marine SES. Socio-economic novelty in the Baltic Sea showed a change in the contribution to novelty from factors linked to local and regional management levels, i.e., fishing gears and commercial groups, to trades which are linked to international level. A high increase in imports and exports in recent years marked the fastest increase in novelty over the period studied. In the latter, novelty in terms of economic value of fishery products was higher than their novelty in quantity. Sweden, Denmark, and Poland have been the countries contributing most to the emergence of novelty in the studied period. This paper illustrates that understanding socio-economic novelty together with ecological novelty, may provide a better understanding of the complexity of marine SES. Although not all the characteristics of CAS could be captured by the methodological approach used in Paper 1 and 2, many have been identified and considered. However, this highlights the need for more methods that can capture different characteristics of CAS, such as interactions and feedbacks, and more knowledge on the emergence of novelty in SES. Understanding how novelty emerges, its processes in different SES components and across-scales, may reduce the risk of missing opportunities for biodiversity conservation, and of unintended management outcomes for long-term sustainability.
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| 2. |
- Ammar, Yosr, et al.
(författare)
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Quantifying socio-economic novelty in fisheries social-ecological systems
- 2022
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Ingår i: Fish and Fisheries. - : Wiley. - 1467-2960 .- 1467-2979. ; 23:2, s. 445-461
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Tidskriftsartikel (refereegranskat)abstract
- Socio-economic development has shaped fisheries social-ecological systems (SES) worldwide across different scales. No work has yet undertaken how this development led to novel, not experienced before, systems structure in marine SES. Here, we quantify socio-economic novelty as the degree of dissimilarity relative to a specific spatiotemporal baseline in the Baltic Sea fisheries SES between 1975 and 2015. We used catch by "gears," catch by "commercial groups" and trade ("import" and "export") as respective indicators of novelty at national, regional and international governance levels. We found that socio-economic novelty increased over time nonlinearly in relation to the 1975–1979 baseline. The contribution to total novelty shifted from the dominance of “gears” and “commercial groups” in the late 1990s and early 2000s to “import” and “export” after the mid-2000s, i.e. from national and regional levels to the international level. The fastest increase in novelty occurred with the trade dominance shift, primarily related to monetary value rather than quantity. Spatially, novelty emerged with a large difference across countries, and a major contribution by Sweden, Denmark and Poland. We identified the influence of different management interventions and governance actions on the emergence of novelty in the Baltic SES. The decreasing socio-economic novelty at national and regional levels could indicate reduced variability due to management intervention in recent years which might decrease SES resilience to shocks. Calculating socio-economic novelty and studying its drivers at different scales could provide a better understanding of SES complexity and inform urgently needed adaptation and transformation towards sustainable future pathways.
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| 3. |
- Ammar, Yosr, et al.
(författare)
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The rise of novelty in marine ecosystems : The Baltic Sea case
- 2021
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Ingår i: Global Change Biology. - : Wiley. - 1354-1013 .- 1365-2486. ; 27:7, s. 1485-1499
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Tidskriftsartikel (refereegranskat)abstract
- Global environmental changes have accelerated at an unprecedented rate in recent decades due to human activities. As a consequence, the incidence of novel abiotic conditions and biotic communities, which have been continuously emerging in the Earth system, has rapidly risen. Despite growing attention to the incidence and challenges posed by novelty in terrestrial ecosystems, novelty has not yet been quantified in marine ecosystems. Here, we measured for the rate of novelty (RoN) in abiotic conditions and community structure for three trophic levels, i.e., phytoplankton, zooplankton, and fish, in a large marine system - the Baltic Sea. We measured RoN as the degree of dissimilarity relative to a specific spatial and temporal baseline, and contrasted this with the rate of change as a measure of within-basin change over time. We found that over the past 35 years abiotic and biotic RoN showed complex dynamics varying in time and space, depending on the baseline conditions. RoN in abiotic conditions was smaller in the open Central Baltic Sea than in the Kattegat and the more enclosed Gulf of Bothnia, Gulf of Riga, and Gulf of Finland in the north. We found a similar spatial pattern for biotic assemblages, which resulted from changes in composition and stock size. We identified sea-surface temperature and salinity as key drivers of RoN in biotic communities. Hence, future environmental changes that are expected to affect the biogeochemistry of the Baltic Sea, may favor the rise of biotic novelty. Our results highlighted the need for a deeper understanding of novelty development in marine ecosystems, including interactions between species and trophic levels, ecosystem functioning under novel abiotic conditions, and considering novelty in future management interventions.
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| 4. |
- Blenckner, Thorsten, et al.
(författare)
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The Baltic Health Index (BHI): Assessing the social-ecological status of the Baltic Sea
- 2021
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Ingår i: People and Nature. - : Wiley. - 2575-8314. ; 3:2, s. 359-375
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Tidskriftsartikel (refereegranskat)abstract
- Improving the health of coastal and open sea marine ecosystems represents a substantial challenge for sustainable marine resource management, since it requires balancing human benefits and impacts on the ocean. This challenge is often exacerbated by incomplete knowledge and lack of tools that measure ocean and coastal ecosystem health in a way that allows consistent monitoring of progress towards predefined management targets. The lack of such tools often limits capabilities to enact and enforce effective governance. We introduce the Baltic Health Index (BHI) as a transparent, collaborative and repeatable assessment tool. The Index complements existing, more ecological-oriented, approaches by including a human dimension on the status of the Baltic Sea, an ecosystem impacted by multiple anthropogenic pressures and governed by a multitude of comprehensive national and international policies. Using a large amount of social-ecological data available, we assessed the health of the Baltic Sea for nine goals that represent the status towards set targets, for example, clean waters, biodiversity, food provision, natural products extraction and tourism. Our results indicate that the overall health of the Baltic Sea is suboptimal (a score of 76 out of 100), and a substantial effort is required to reach the management objectives and associated targets. Subregionally, the lowest BHI scores were measured for carbon storage, contaminants and lasting special places (i.e. marine protected areas), albeit with large spatial variation. Overall, the likely future status of all goals in the BHI averaged for the entire Baltic Sea is better than the present status, indicating a positive trend towards a healthier Baltic Sea. However, in some Baltic Sea basins, the trend for specific goals was decreasing, highlighting locations and issues that should be the focus of management priorities. The BHI outcomes can be used to identify both pan-Baltic and subregional scale management priorities and to illustrate the interconnectedness between goals linked by cumulative pressures. Hence, the information provided by the BHI tool and its further development will contribute towards the fulfilment of the UN Agenda 2030 and its Sustainability Development Goals. A free Plain Language Summary can be found within the Supporting Information of this article. A free Plain Language Summary can be found within the Supporting Information of this article.
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| 5. |
- Blenckner, Thorsten, et al.
(författare)
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The Risk for Novel and Disappearing Environmental Conditions in the Baltic Sea
- 2021
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Ingår i: Frontiers in Marine Science. - : Frontiers Media SA. - 2296-7745. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- Future climate biogeochemical projections indicate large changes in the ocean with environmental conditions not experienced at present referred to as novel, or may even disappear. These climate-induced changes will most likely affect species distribution via changes in growth, behavior, evolution, dispersal, and species interactions. However, the future risk of novel and disappearing environmental conditions in the ocean is poorly understood, in particular for compound effects of climate and nutrient management changes. We map the compound risk of the occurrence of future novel and disappearing environmental conditions, analyze the outcome of climate and nutrient management scenarios for the world’s largest estuary, the Baltic Sea, and the potential consequences for three charismatic species. Overall, the future projections show, as expected, an increase in environmental novelty over time. The future nutrient reduction management that improves the eutrophication status of the Baltic Sea contributes to large novel and disappearing conditions. We show the consequences of novel and disappearing environmental conditions for fundamental niches of three charismatic species under different scenarios. This first step toward comprehensively analyzing environmental novelty and disappearing conditions for a marine system illustrates the urgent need to include novelty and disappearing projection outputs in Earth System Models. Our results further illustrate that adaptive management is needed to account for the emergence of novelty related to the interplay of multiple drivers. Overall, our analysis provides strong support for the expectation of novel ecological communities in marine systems, which may affect ecosystem services, and needs to be accounted for in sustainable future management plans of our oceans.
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| 6. |
- Daewel, Ute, et al.
(författare)
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Predation control of zooplankton dynamics : a review of observations and models
- 2014
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Ingår i: ICES Journal of Marine Science. - : Oxford University Press (OUP). - 1054-3139 .- 1095-9289. ; 71:2, s. 254-271
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Forskningsöversikt (refereegranskat)abstract
- We performed a literature review to examine to what degree the zooplankton dynamics in different regional marine ecosystems across the Atlantic Ocean is driven by predation mortality and how the latter is addressed in available modelling approaches. In general, we found that predation on zooplankton plays an important role in all the six considered ecosystems, but the impacts are differently strong and occur at different spatial and temporal scales. In ecosystems with extreme environmental conditions (e.g. low temperature, ice cover, large seasonal amplitudes) and low species diversity, the overall impact of top-down processes on zooplankton dynamics is stronger than for ecosystems having moderate environmental conditions and high species diversity. In those ecosystems, predation mortality was found to structure the zooplankton mainly on local spatial and seasonal time scales. Modelling methods used to parameterize zooplankton mortality range from simplified approaches with fixed mortality rates to complex coupled multispecies models. The applicability of a specific method depends on both the observed state of the ecosystem and the spatial and temporal scales considered. Modelling constraints such as parameter uncertainties and computational costs need to be balanced with the ecosystem-specific demand for a consistent, spatial-temporal dynamic implementation of predation mortality on the zooplankton compartment.
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| 7. |
- Griffiths, Jennifer R., et al.
(författare)
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The importance of benthic-pelagic coupling for marine ecosystem functioning in a changing world
- 2017
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Ingår i: Global Change Biology. - : Wiley. - 1354-1013 .- 1365-2486. ; 23:6, s. 2179-2196
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Forskningsöversikt (refereegranskat)abstract
- Benthic-pelagic coupling is manifested as the exchange of energy, mass, or nutrients between benthic and pelagic habitats. It plays a prominent role in aquatic ecosystems, and it is crucial to functions from nutrient cycling to energy transfer in food webs. Coastal and estuarine ecosystem structure and function are strongly affected by anthropogenic pressures; however, there are large gaps in our understanding of the responses of inorganic nutrient and organic matter fluxes between benthic habitats and the water column. We illustrate the varied nature of physical and biological benthic-pelagic coupling processes and their potential sensitivity to three anthropogenic pressures - climate change, nutrient loading, and fishing - using the Baltic Sea as a case study and summarize current knowledge on the exchange of inorganic nutrients and organic material between habitats. Traditionally measured benthic-pelagic coupling processes (e.g., nutrient exchange and sedimentation of organic material) are to some extent quantifiable, but the magnitude and variability of biological processes are rarely assessed, preventing quantitative comparisons. Changing oxygen conditions will continue to have widespread effects on the processes that govern inorganic and organic matter exchange among habitats while climate change and nutrient load reductions may have large effects on organic matter sedimentation. Many biological processes (predation, bioturbation) are expected to be sensitive to anthropogenic drivers, but the outcomes for ecosystem function are largely unknown. We emphasize how improved empirical and experimental understanding of benthic-pelagic coupling processes and their variability are necessary to inform models that can quantify the feedbacks among processes and ecosystem responses to a changing world.
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| 8. |
- Gårdmark, Anna, et al.
(författare)
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Biological ensemble modeling to evaluate potential futures of living marine resources
- 2013
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Ingår i: Ecological Applications. - : Wiley. - 1051-0761 .- 1939-5582. ; 23:4, s. 742-754
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Tidskriftsartikel (refereegranskat)abstract
- Natural resource management requires approaches to understand and handle sources of uncertainty in future responses of complex systems to human activities. Here we present one such approach, the biological ensemble modeling approach,'' using the Eastern Baltic cod (Gadus morhua callarias) as an example. The core of the approach is to expose an ensemble of models with different ecological assumptions to climate forcing, using multiple realizations of each climate scenario. We simulated the long-term response of cod to future fishing and climate change in seven ecological models ranging from single-species to food web models. These models were analyzed using the biological ensemble modeling approach'' by which we (1) identified a key ecological mechanism explaining the differences in simulated cod responses between models, (2) disentangled the uncertainty caused by differences in ecological model assumptions from the statistical uncertainty of future climate, and (3) identified results common for the whole model ensemble. Species interactions greatly influenced the simulated response of cod to fishing and climate, as well as the degree to which the statistical uncertainty of climate trajectories carried through to uncertainty of cod responses. Models ignoring the feedback from prey on cod showed large interannual fluctuations in cod dynamics and were more sensitive to the underlying uncertainty of climate forcing than models accounting for such stabilizing predator-prey feedbacks. Yet in all models, intense fishing prevented recovery, and climate change further decreased the cod population. Our study demonstrates how the biological ensemble modeling approach makes it possible to evaluate the relative importance of different sources of uncertainty in future species responses, as well as to seek scientific conclusions and sustainable management solutions robust to uncertainty of food web processes in the face of climate change.
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| 9. |
- Havenhand, Jonathan N., 1959, et al.
(författare)
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Ecological and functional consequences of coastal ocean acidification : Perspectives from the Baltic-Skagerrak System
- 2019
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Ingår i: Ambio. - : Springer Science and Business Media LLC. - 0044-7447 .- 1654-7209. ; 48:8, s. 831-854
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Forskningsöversikt (refereegranskat)abstract
- Ocean temperatures are rising; species are shifting poleward, and pH is falling (ocean acidification, OA). We summarise current understanding of OA in the brackish Baltic-Skagerrak System, focussing on the direct, indirect and interactive effects of OA with other anthropogenic drivers on marine biogeochemistry, organisms and ecosystems. Substantial recent advances reveal a pattern of stronger responses (positive or negative) of species than ecosystems, more positive responses at lower trophic levels and strong indirect interactions in food-webs. Common emergent themes were as follows: OA drives planktonic systems toward the microbial loop, reducing energy transfer to zooplankton and fish; and nutrient/food availability ameliorates negative impacts of OA. We identify several key areas for further research, notably the need for OA-relevant biogeochemical and ecosystem models, and understanding the ecological and evolutionary capacity of Baltic-Skagerrak ecosystems to respond to OA and other anthropogenic drivers.
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| 10. |
- Kadin, Martina, et al.
(författare)
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Linking demographic and food-web models to understand management trade-offs
- 2019
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Ingår i: Ecology and Evolution. - : Wiley. - 2045-7758. ; 9:15, s. 8587-8600
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Tidskriftsartikel (refereegranskat)abstract
- Alternatives in ecosystem-based management often differ with respect to trade-offs between ecosystem values. Ecosystem or food-web models and demographic models are typically employed to evaluate alternatives, but the approaches are rarely integrated to uncover conflicts between values. We applied multistate models to a capture-recapture dataset on common guillemots Uria aalge breeding in the Baltic Sea to identify factors influencing survival. The estimated relationships were employed together with Ecopath-with-Ecosim food-web model simulations to project guillemot survival under six future scenarios incorporating climate change. The scenarios were based on management alternatives for eutrophication and cod fisheries, issues considered top priority for regional management, but without known direct effects on the guillemot population. Our demographic models identified prey quantity (abundance and biomass of sprat Sprattus sprattus) as the main factor influencing guillemot survival. Most scenarios resulted in projections of increased survival, in the near (2016-2040) and distant (2060-2085) future. However, in the scenario of reduced nutrient input and precautionary cod fishing, guillemot survival was projected to be lower in both future periods due to lower sprat stocks. Matrix population models suggested a substantial decline of the guillemot population in the near future, 24% per 10 years, and a smaller reduction, 1.1% per 10 years, in the distant future. To date, many stakeholders and Baltic Sea governments have supported reduced nutrient input and precautionary cod fishing and implementation is underway. Negative effects on nonfocal species have previously not been uncovered, but our results show that the scenario is likely to negatively impact the guillemot population. Linking model results allowed identifying trade-offs associated with management alternatives. This information is critical to thorough evaluation by decision-makers, but not easily obtained by food-web models or demographic models in isolation. Appropriate datasets are often available, making it feasible to apply a linked approach for better-informed decisions in ecosystem-based management.
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