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Papers by karen Timmermann
Predicting eider predation potentials on mussels in Danish coastal areas—implications for mussel farming site-selection
Aquaculture Environment Interactions, Mar 30, 2023
Agronomy, Jan 17, 2023
Manure acidification has been introduced as an abatement to reduce ammonia (NH 3 ) emissions to i... more Manure acidification has been introduced as an abatement to reduce ammonia (NH 3 ) emissions to improve air quality and protect terrestrial and aquatic environments from nitrogen deposition. A successful regulation of NH 3 emissions using manure acidification might, however, result in increased nitrogen leaching from fertilized fields with adverse effects on freshwater and marine ecosystems, if the overall fertilizer application rate in the fields is not adjusted according to the increased fertilizer value of the manure. We apply a holistic model framework encapsulating all important environmental compartments to assess the ecological and economic consequences of a specific agricultural practice or a combination of these. The results show that manure acidification combined with air cleaners reduces NH 3 emission and atmospheric nitrogen deposition with substantial positive effects on the terrestrial environment. Although manure acidification results in a slight increase in total nitrogen input into freshwater and marine ecosystems, the subsequent increase in chlorophyll a concentration and decrease in water transparency is insignificant. Hence, according to the model results, manure acidification will improve terrestrial nature quality, with no significant adverse effects on the aquatic environments.
The Mytilus edulis (Blue Mussel) Mitigation Farm Site Selection Tool for the Western Baltic Sea (... more The Mytilus edulis (Blue Mussel) Mitigation Farm Site Selection Tool for the Western Baltic Sea (MYTIGATE) is meant to provide stakeholders with a science-based decision support tool that offers flexible site selection solutions. Site selection is based on customized input criteria and, therefore fully dynamic with respect to the user's selections. MYTIGATE is based on 'a spatial model for nutrient mitigation potential of blue mussel farms in the western Baltic Sea' and a thorough selection of available spatial data about utilization of the respective marine areas. It works on a spatial resolution of 1x1 km 2 pixels. Within the tool, users can select specific areas of interest, investigate the model input parameters and results, adapt aquaculture farm setup, specify criteria for site-exclusion, set individual weights on potential conflict criteria, and define a specific criterion for the generated siteselection scenario. MYTIGATE uses an algorithm that integrates the spatial model result for the selection criterion (e.g. mussel weight, farm harvest) with locally applying exclusion and weighted conflict criteria. The algorithm then generates a ranking among all available sites, and selects the adequate number of most suitable sites until the selection target (e.g. no. of farms, nitrogen reduction) is reached. MYTIGATE will always only place one mitigation farm within each 1x1 km 2 pixel. A summary of the selection results is reported, a respective map is created, and detailed information on the selected sites can be downloaded as a table.
Muslinger som marint virkemiddel til fjernelse af næringsstoffer – miljøeffekter på fjordskala
Marine virkemidler og N/P - status 2020
Vand & Jord, 2020
Marine application of the Danish EPA’s Marine Model Complex and Development of a Method Applicable for the River Basin Management Plans 2021-2027.: Improved growth conditions in selected estuaries based on 30% reductions in land based nutrient loads
Water Resources and Economics, 2020
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Muslinger som marint virkemiddel til fjernelse af næringsstoffer – miljøeffekter på fjordskala
SYMBIOSE:Ecologically relevant data for marine strategies
Payment for ecosystem services - paying mussel producers for nitrogen mitigation
Kari Eilola, Swedish Meteorological and Hydrological Institute Sven Källfelts gata 15, SE-426 71 ... more Kari Eilola, Swedish Meteorological and Hydrological Institute Sven Källfelts gata 15, SE-426 71 V Frölunda, Sweden Telephone +46(0)31 7518963 E-mail kari.eilola@smhi.se
Beskrivelser af marine virkemidler: Muslingeopdræt
Aarhus Universitet, DCE – Nationalt Center for Miljø og Energi ©, 2020
Arenicola marinas bioturbation påvirker skæbnen af en kompleks sedimentforurening:et feltforsøg med olieforurenet sediment
Limnology and Oceanography, 2021
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Frontiers in Marine Science, 2020
Coastal seas are highly productive systems, providing an array of ecosystem services to humankind... more Coastal seas are highly productive systems, providing an array of ecosystem services to humankind, such as processing of nutrient effluents from land and climate regulation. However, coastal ecosystems are threatened by human-induced pressures such as climate change and eutrophication. In the coastal zone, the fluxes and transformations of nutrients and carbon sustaining coastal ecosystem functions and services are strongly regulated by benthic biological and chemical processes. Thus, to understand and quantify how coastal ecosystems respond to environmental change, mechanistic modeling of benthic biogeochemical processes is required. Here, we discuss the present model capabilities to quantitatively describe how benthic fauna drives nutrient and carbon processing in the coastal zone. There are a multitude of modeling approaches of different complexity, but a thorough mechanistic description of benthic-pelagic processes is still hampered by a fundamental lack of scientific understanding of the diverse interactions between the physical, chemical and biological processes that drive biogeochemical fluxes in the coastal zone. Especially shallow systems with long water residence times are sensitive to the activities of benthic organisms. Hence, including and improving the description of benthic biomass and metabolism in sediment diagenetic as well as ecosystem models for such systems is essential to increase our understanding of their response to environmental changes and the role of coastal sediments in nutrient and carbon cycling. Major challenges and research priorities are (1) to couple the dynamics of zoobenthic biomass and metabolism to sediment reactive-transport in models, (2) to test and validate model formulations against real-world data to better incorporate the context-dependency of processes in heterogeneous coastal areas in models and (3) to capture the role of stochastic events.
Bristleworms affect pollutions in the sea bottom: Model studies with pyrene [infauna, bioturbation]
Modelling macrofaunal biomass in relation to hypoxia and nutrient loading
Journal of Marine Systems, 2012
ABSTRACT Nutrient loading of aquatic ecosystems results in more food for benthic macrofaunal comm... more ABSTRACT Nutrient loading of aquatic ecosystems results in more food for benthic macrofaunal communities but also increases the risk of hypoxia, resulting in a reduction or complete loss of benthic biomass. This study inves-tigates the interaction between eutrophication, hypoxia and benthic biomass with emphasis on the balance between gains and loss of benthic biomass due to changes in nutrient loadings. A physiological fauna model with 5 functional groups was linked to a 3D coupled hydrodynamic–ecological Baltic Sea model. Model results revealed that benthic biomass increased between 0 and 700% after re-oxygenating bottom wa-ters. Nutrient reduction scenarios indicated improved oxygen concentrations in bottom waters and de-creased sedimentation of organic matter up to 40% after a nutrient load reduction following the Baltic Sea Action Plan. The lower food supply to benthos reduced the macrofaunal biomass up to 35% especially in areas not currently affected by hypoxia, whereas benthic biomass increased up to 200% in areas affected by eutrophication-induced hypoxia. The expected changes in benthic biomass resulting from nutrient load re-ductions and subsequent reduced hypoxia may not only increase the food supply for benthivorous fish, but also significantly affect the biogeochemical functioning of the ecosystem.
Global Change Biology, 2011
Invasive species and bottom-water hypoxia both constitute major global threats to the diversity a... more Invasive species and bottom-water hypoxia both constitute major global threats to the diversity and integrity of marine ecosystems. These stressors may interact with unexpected consequences, as invasive species that require an initial environmental disturbance to become established can subsequently become important drivers of ecological change. There is recent evidence that improved bottom-water oxygen conditions in coastal areas of the northern Baltic Sea coincide with increased abundances of the invasive polychaetes Marenzelleria spp. Using a reactive-transport model, we demonstrate that the long-term bioirrigation activities of dense Marenzelleria populations have a major impact on sedimentary phosphorus dynamics. This may facilitate the switch from a seasonally hypoxic system back to a normoxic system by reducing the potential for sediment-induced eutrophication in the upper water column. In contrast to short-term laboratory experiments, our simulations, which cover a 10-year period, show that Marenzelleria has the potential to enhance long-term phosphorus retention in muddy sediments. Over time bioirrigation leads to a substantial increase in the iron-bound phosphorus content of sediments while reducing the concentration of labile organic carbon. As surface sediments are maintained oxic, iron oxyhydroxides are able to persist and age into more refractory forms. The model illustrates mechanisms through which Marenzelleria can act as a driver of ecological change, although hypoxic disturbance or natural population declines in native species may be needed for them to initially become established. Invasive species are generally considered to have a negative impact; however, we show here that one of the main recent invaders in the Baltic Sea may provide important ecosystem services. This may be of particular importance in low-diversity systems, where disturbances may dramatically alter ecosystem services due to low functional redundancy. Thus, an environmental problem in one region may be either exacerbated or alleviated by a single species from another region, with potentially ecosystem-wide consequences.
Predicting eider predation potentials on mussels in Danish coastal areas—implications for mussel farming site-selection
Aquaculture Environment Interactions, Mar 30, 2023
Agronomy, Jan 17, 2023
Manure acidification has been introduced as an abatement to reduce ammonia (NH 3 ) emissions to i... more Manure acidification has been introduced as an abatement to reduce ammonia (NH 3 ) emissions to improve air quality and protect terrestrial and aquatic environments from nitrogen deposition. A successful regulation of NH 3 emissions using manure acidification might, however, result in increased nitrogen leaching from fertilized fields with adverse effects on freshwater and marine ecosystems, if the overall fertilizer application rate in the fields is not adjusted according to the increased fertilizer value of the manure. We apply a holistic model framework encapsulating all important environmental compartments to assess the ecological and economic consequences of a specific agricultural practice or a combination of these. The results show that manure acidification combined with air cleaners reduces NH 3 emission and atmospheric nitrogen deposition with substantial positive effects on the terrestrial environment. Although manure acidification results in a slight increase in total nitrogen input into freshwater and marine ecosystems, the subsequent increase in chlorophyll a concentration and decrease in water transparency is insignificant. Hence, according to the model results, manure acidification will improve terrestrial nature quality, with no significant adverse effects on the aquatic environments.
The Mytilus edulis (Blue Mussel) Mitigation Farm Site Selection Tool for the Western Baltic Sea (... more The Mytilus edulis (Blue Mussel) Mitigation Farm Site Selection Tool for the Western Baltic Sea (MYTIGATE) is meant to provide stakeholders with a science-based decision support tool that offers flexible site selection solutions. Site selection is based on customized input criteria and, therefore fully dynamic with respect to the user's selections. MYTIGATE is based on 'a spatial model for nutrient mitigation potential of blue mussel farms in the western Baltic Sea' and a thorough selection of available spatial data about utilization of the respective marine areas. It works on a spatial resolution of 1x1 km 2 pixels. Within the tool, users can select specific areas of interest, investigate the model input parameters and results, adapt aquaculture farm setup, specify criteria for site-exclusion, set individual weights on potential conflict criteria, and define a specific criterion for the generated siteselection scenario. MYTIGATE uses an algorithm that integrates the spatial model result for the selection criterion (e.g. mussel weight, farm harvest) with locally applying exclusion and weighted conflict criteria. The algorithm then generates a ranking among all available sites, and selects the adequate number of most suitable sites until the selection target (e.g. no. of farms, nitrogen reduction) is reached. MYTIGATE will always only place one mitigation farm within each 1x1 km 2 pixel. A summary of the selection results is reported, a respective map is created, and detailed information on the selected sites can be downloaded as a table.
Muslinger som marint virkemiddel til fjernelse af næringsstoffer – miljøeffekter på fjordskala
Marine virkemidler og N/P - status 2020
Vand & Jord, 2020
Marine application of the Danish EPA’s Marine Model Complex and Development of a Method Applicable for the River Basin Management Plans 2021-2027.: Improved growth conditions in selected estuaries based on 30% reductions in land based nutrient loads
Water Resources and Economics, 2020
This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Muslinger som marint virkemiddel til fjernelse af næringsstoffer – miljøeffekter på fjordskala
SYMBIOSE:Ecologically relevant data for marine strategies
Payment for ecosystem services - paying mussel producers for nitrogen mitigation
Kari Eilola, Swedish Meteorological and Hydrological Institute Sven Källfelts gata 15, SE-426 71 ... more Kari Eilola, Swedish Meteorological and Hydrological Institute Sven Källfelts gata 15, SE-426 71 V Frölunda, Sweden Telephone +46(0)31 7518963 E-mail kari.eilola@smhi.se
Beskrivelser af marine virkemidler: Muslingeopdræt
Aarhus Universitet, DCE – Nationalt Center for Miljø og Energi ©, 2020
Arenicola marinas bioturbation påvirker skæbnen af en kompleks sedimentforurening:et feltforsøg med olieforurenet sediment
Limnology and Oceanography, 2021
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Frontiers in Marine Science, 2020
Coastal seas are highly productive systems, providing an array of ecosystem services to humankind... more Coastal seas are highly productive systems, providing an array of ecosystem services to humankind, such as processing of nutrient effluents from land and climate regulation. However, coastal ecosystems are threatened by human-induced pressures such as climate change and eutrophication. In the coastal zone, the fluxes and transformations of nutrients and carbon sustaining coastal ecosystem functions and services are strongly regulated by benthic biological and chemical processes. Thus, to understand and quantify how coastal ecosystems respond to environmental change, mechanistic modeling of benthic biogeochemical processes is required. Here, we discuss the present model capabilities to quantitatively describe how benthic fauna drives nutrient and carbon processing in the coastal zone. There are a multitude of modeling approaches of different complexity, but a thorough mechanistic description of benthic-pelagic processes is still hampered by a fundamental lack of scientific understanding of the diverse interactions between the physical, chemical and biological processes that drive biogeochemical fluxes in the coastal zone. Especially shallow systems with long water residence times are sensitive to the activities of benthic organisms. Hence, including and improving the description of benthic biomass and metabolism in sediment diagenetic as well as ecosystem models for such systems is essential to increase our understanding of their response to environmental changes and the role of coastal sediments in nutrient and carbon cycling. Major challenges and research priorities are (1) to couple the dynamics of zoobenthic biomass and metabolism to sediment reactive-transport in models, (2) to test and validate model formulations against real-world data to better incorporate the context-dependency of processes in heterogeneous coastal areas in models and (3) to capture the role of stochastic events.
Bristleworms affect pollutions in the sea bottom: Model studies with pyrene [infauna, bioturbation]
Modelling macrofaunal biomass in relation to hypoxia and nutrient loading
Journal of Marine Systems, 2012
ABSTRACT Nutrient loading of aquatic ecosystems results in more food for benthic macrofaunal comm... more ABSTRACT Nutrient loading of aquatic ecosystems results in more food for benthic macrofaunal communities but also increases the risk of hypoxia, resulting in a reduction or complete loss of benthic biomass. This study inves-tigates the interaction between eutrophication, hypoxia and benthic biomass with emphasis on the balance between gains and loss of benthic biomass due to changes in nutrient loadings. A physiological fauna model with 5 functional groups was linked to a 3D coupled hydrodynamic–ecological Baltic Sea model. Model results revealed that benthic biomass increased between 0 and 700% after re-oxygenating bottom wa-ters. Nutrient reduction scenarios indicated improved oxygen concentrations in bottom waters and de-creased sedimentation of organic matter up to 40% after a nutrient load reduction following the Baltic Sea Action Plan. The lower food supply to benthos reduced the macrofaunal biomass up to 35% especially in areas not currently affected by hypoxia, whereas benthic biomass increased up to 200% in areas affected by eutrophication-induced hypoxia. The expected changes in benthic biomass resulting from nutrient load re-ductions and subsequent reduced hypoxia may not only increase the food supply for benthivorous fish, but also significantly affect the biogeochemical functioning of the ecosystem.
Global Change Biology, 2011
Invasive species and bottom-water hypoxia both constitute major global threats to the diversity a... more Invasive species and bottom-water hypoxia both constitute major global threats to the diversity and integrity of marine ecosystems. These stressors may interact with unexpected consequences, as invasive species that require an initial environmental disturbance to become established can subsequently become important drivers of ecological change. There is recent evidence that improved bottom-water oxygen conditions in coastal areas of the northern Baltic Sea coincide with increased abundances of the invasive polychaetes Marenzelleria spp. Using a reactive-transport model, we demonstrate that the long-term bioirrigation activities of dense Marenzelleria populations have a major impact on sedimentary phosphorus dynamics. This may facilitate the switch from a seasonally hypoxic system back to a normoxic system by reducing the potential for sediment-induced eutrophication in the upper water column. In contrast to short-term laboratory experiments, our simulations, which cover a 10-year period, show that Marenzelleria has the potential to enhance long-term phosphorus retention in muddy sediments. Over time bioirrigation leads to a substantial increase in the iron-bound phosphorus content of sediments while reducing the concentration of labile organic carbon. As surface sediments are maintained oxic, iron oxyhydroxides are able to persist and age into more refractory forms. The model illustrates mechanisms through which Marenzelleria can act as a driver of ecological change, although hypoxic disturbance or natural population declines in native species may be needed for them to initially become established. Invasive species are generally considered to have a negative impact; however, we show here that one of the main recent invaders in the Baltic Sea may provide important ecosystem services. This may be of particular importance in low-diversity systems, where disturbances may dramatically alter ecosystem services due to low functional redundancy. Thus, an environmental problem in one region may be either exacerbated or alleviated by a single species from another region, with potentially ecosystem-wide consequences.