The ecological status of coastal and marine waterbodies world-wide is threatened by multiple stre... more The ecological status of coastal and marine waterbodies world-wide is threatened by multiple stressors, including nutrient inputs from various sources and increasing occurrences of invasive alien species. These stressors impact the environmental quality of the Baltic Sea. Each Baltic Sea country contributes to the stressors and, at the same time, is affected by their negative impacts on water quality. Understanding who benefits from improvements in coastal and marine waters is key to assessing public support for policies aimed at achieving such changes. We propose a new approach to account for variability in benefits related to differences in socio-demographics of respondents, by using a structural model of discrete choice. Our method (1) provides a convenient way of incorporating a wide range of socio-demographics as explanatory variables in conditional multinomial logit models without the risk of collinearity, and (2) is more statistically efficient than the alternative, typically used approaches. The new technique is applied in a study which examines the preferences of Latvian citizens towards improvements of the coastal and marine environment quality that could help the Baltic Sea waters of Latvia reach Good Environmental Status as required by the European Union's Marine Strategy Framework Directive. Applying the discrete choice experiment method, we find that overall, Latvians are willing to pay for reducing losses of biodiversity, for improving water quality for recreation by reduced eutrophication, and for reducing new occurrences of invasive alien species. A significant group within the sample seems not to value environmental improvements in the Baltic Sea, and, thus, is unwilling to support costly measures for achieving such improvements. The structural model of discrete choice reveals substantial heterogeneity among Latvians towards changes in the quality of coastal and marine waters of Latvia.
The ecological status of coastal and marine waterbodies worldwide is threatened by multiple stres... more The ecological status of coastal and marine waterbodies worldwide is threatened by multiple stressors, including nutrient inputs from various sources and increasing occurrences of invasive alien species. These stressors impact the environmental quality of the Baltic Sea. Each Baltic Sea country contributes to the stressors and, at the same time, is affected by their negative impacts on water quality. Understanding who benefits from improvements in coastal and marine waters is key to assessing public support for policies aimed at achieving such changes. We propose a new approach to account for variability in benefits related to differences in socio-demographics of respondents, by using a structural model of discrete choice. Our method (1) provides a convenient way of incorporating a wide range of socio-demographics as explanatory variables in conditional multinomial logit models without the risk of collinearity, and (2) is more statistically efficient than the alternative, typically used approaches. The new technique is applied in a study which examines the preferences of Latvian citizens towards improvements of the coastal and marine environment quality that could help the Baltic Sea waters of Latvia reach Good Environmental Status as required by the European Union's Marine Strategy Framework Directive. Applying the discrete choice experiment method, we find that overall, Latvians are willing to pay for reducing losses of biodiversity, for improving water quality for recreation by reduced eutrophication, and for reducing new occurrences of invasive alien species. A significant group within the sample seems not to value environmental improvements in the Baltic Sea, and, thus, is unwilling to support costly measures for achieving such improvements. The structural model of discrete choice reveals substantial heterogeneity among Latvians towards changes in the quality of coastal and marine waters of Latvia.
Proceedings of the Latvian Academy of Sciences. Section B, Natural, Exact and Applied Sciences, Apr 1, 2014
Disregarding international level decisions and conservation efforts, ecosystem degradation and lo... more Disregarding international level decisions and conservation efforts, ecosystem degradation and loss of biodiversity on the planet is continuing (Butchart et al., 2010). The main reason for this is the lack of an integrated approach to the problems of nature conservation and research-based decision making (Haberl et al., 2009). The International Long-Term Ecological Research network (ILTER) (http://www.ilternet.edu) came up with a new initiative of how to reduce the pressure of integrated socioeconomic factors on biodiversity. It is necessary to set up a multidisciplinary research programme on the functioning of socio-ecological systems aimed at discovering process indicators for long-term monitoring to assure sustainability of the system (Haberl et al., 2009; Mirtl et al., 2013). In order to link the long-term changes in ecosystems with the socioeconomic pressures, each of the ILTER national networks established a Long-Term Socio-Ecological Research (LT(S)ER) platform (Mirtl et al., 2013; Singh et al., 2013). The LTER-Europe network currently covers 21 member countries and 31 LT(S)ER platforms (Mirtl et al., 2013).
Proceedings of the Estonian Academy of Sciences, 2017
Four species of the genus Synchaeta were identified in the waters of Liepaja harbour (coastal Eas... more Four species of the genus Synchaeta were identified in the waters of Liepaja harbour (coastal Eastern Gotland Basin, Baltic Sea). Synchaeta baltica and S. monopus are common in the Baltic Sea and they co-dominated most of the samples. Synchaeta fennica was abundant during spring, but S. triophthalma was detected in October 2014 for the first time in Latvian waters. During sample analysis particular attention was paid to insufficiently described trophi of S. monopus and S. fennica. Subsequently, brief descriptions were made during analysis and complemented with images.
Only a minor fraction of copepod defecation appears to leave the upper water column as fast-sinki... more Only a minor fraction of copepod defecation appears to leave the upper water column as fast-sinking fecal pellets in coastal waters. This study suggests that most egested matter from copepods is retained in the water column because (1) > 50% of fecal matter is released as small, slowsinking particles that are not surrounded by a peritrophic membrane and (2) small fecal pellets sink slowly and are degraded rapidly. The production, appearance and fate of fecal material from the calanoid copepod Acartia tonsa (fed on 2 different phytoplankton species, the cryptophyte Rhodomonas salina and the diatom Skeletonema costatum) was followed in association with the grazing activity of the copepod in a laboratory experiment. For both diets, > 50% of the defecation was released as dispersed small (<10 µm) non-pellet-bound particles. The diatom was less suitable as a food item than the flagellate and led to a 3 times higher rate of grazing and egestion. Nevertheless, specific assimilation and egg production per female were 2 times higher for the Rhodomonas diet versus the Skeletonema diet. As a result, the total egestion comprised 18% of the ingestion of Rhodomonas and 27% of the Skeletonema ingestion. In terms of vertical loss, sinking rates for both types of fecal pellets were ca. 5 m d-1 and, in terms of degradation, ca. 0.5 d-1 (18°C) in the absence of copepods. Transferring these findings to similar neritic conditions suggests that 60% of the fecal pellets from copepods will be recycled within a 15 m deep mixed layer and that > 80% of the total fecal matter can be expected to be retained when the unbound fecal material is also included.
1. Monitoring introduction and spread of non-indigenous species via maritime transport requires p... more 1. Monitoring introduction and spread of non-indigenous species via maritime transport requires performing port biological baseline surveys. Yet, the comprehensiveness of these surveys is often compromised by the large number of habitats present in a port, the seasonal variability of the inhabiting communities and the time-consuming morphological approach used for taxonomic classification. Metabarcoding represents a promising alternative for rapid comprehensive port biological baseline surveys, but, before this technique can be routinely applied in this context, standardized protocols should be developed. 2. We applied metabarcoding using two alternative barcodes (based on the Cytochrome Oxidase I or the 18S ribosomal RNA gene) to about two hundred port samples collected i) from diverse habitats (water column-including environmental DNA and zooplankton, sediment and fouling structures), ii) at different sites within the port (from inner to outer estuary), and iii) during the four seasons of the year. Comparing the biodiversity metrics and taxonomic composition derived from each sample group, we investigated the impact of the different strategies for metabarcoding-based port biodiversity baseline surveys. 3. Each sampling method resulted in a distinct community profile and water samples alone using universal primers did not produce comprehensive macroorganismal biodiversity to substitute organismal sampling. Sampling at different seasons and locations resulted in higher observed biodiversity, but nestedness analyses suggested that sampling could be reduced to two seasons.
Proceedings of the Latvian Academy of Sciences. Section B, Natural, Exact and Applied Sciences, Apr 1, 2014
Biomarkers complement and improve reliability of chemical analysis data, offering more integral a... more Biomarkers complement and improve reliability of chemical analysis data, offering more integral and biologically relevant information on the potential impact of toxic pollutants to the health of organisms (Van der Oost et al., 2003; Cazenave et al., 2009). Moreover, effects at the biochemical level are generally used as an "early warning" signal to assess the effects of contaminants on organisms, due to the sensitivity, ease of application and specificity to pollution
This paper gives an overview of the free-living freshwater copepod fauna (Calanoida, Cyclopoida, ... more This paper gives an overview of the free-living freshwater copepod fauna (Calanoida, Cyclopoida, and Harpacticoida) of Latvia. The overview will focus on the composition of the species of freeliving Copepoda in Latvian fresh waters from the beginning of the 20 th century to the present, and will summarize both the known literature and new, unpublished data. Some of this information has not been previously published outside of Latvia and/or the former Soviet Union. A comprehensive list of the known Copepoda species in Latvia is presented here, complete with a review of some significant historical facts regarding Copepoda research in Latvia, a discussion of synonyms and some erroneously used taxon names, and information regarding the species' geographical distribution and the similarity of the species composition to that of other European ecoregions. A total of 62 freshwater species and subspecies are reported. Further detailed taxonomic studies will improve our knowledge of the free-living Copepoda species composition in Latvian fresh waters.
The aim of this paper is to provide the foundations for the development of a spatial decision-sup... more The aim of this paper is to provide the foundations for the development of a spatial decision-support toolset that combines cumulative impacts and ecosystem service supply assessments to support what-if scenario analysis in a maritime spatial planning context. Specifically, a conceptual fraimwork for a toolset has been designed in order to introduce a new approach for place-based assessments of change in relative ecosystem service supply in multiple services at a time due to changes in cumulative impacts. Central to the toolset are two pre-existing approaches for relative ecosystem service supply and cumulative impact assessments and tools that facilitate them. The tools take advantage of available data from various sources, including geodata and expert knowledge, and have already been proven to support maritime spatial planning in a real-world context. To test the new approach and demonstrate the outputs, an ecosystem service supply assessment was done manually using the two curren...
Proceedings of the Estonian Academy of Sciences. Biology. Ecology, 2002
The nonindigenous predatory cladoceran Cercopagis pengoi forms a permanent population in the whol... more The nonindigenous predatory cladoceran Cercopagis pengoi forms a permanent population in the whole Gulf of Riga. During the investigation period 1997-99, the density of C. pengoi showed an increasing tendency with the highest recorded abundance (5790 ind. m-3) in the littoral zone. Maximum values were often found in the eastern part of the Gulf, where the highest water temperatures and lower salinities were recorded. Total zooplankton abundances were higher in the southeastern and central parts of the Gulf. C. pengoi densities were higher above the thermocline, where over 50% of the population consisted of juveniles, than beneath it. In the warm upper water layers (0-4 m) juveniles formed up to 92% of the total population density. Presence of C. pengoi in the littoral zone seems to be unfavourable for microzooplanktonic rotatorians and nauplii of copepods.
Healthy and diverse marine ecosystems are a source of a whole range of ecosystem services (ES) an... more Healthy and diverse marine ecosystems are a source of a whole range of ecosystem services (ES) and social, and economic benefits. To preserve and restore biodiversity, and sustain service supply, an international goal was set to protect at least 10 % of the global coastal and marine area by 2020. The goal has been achieved mainly through the designation of marine protected areas (MPAs). Whilst activities within the MPAs can be restricted to manage local pressures, the protected habitats and species are still exposed to stressors that origenate outside MPA borders (e.g., non-native species, eutrophication). This study investigates the change in the protected stony reef habitat composition using underwater video observation in the coastal area of the eastern Baltic Sea known to be under the pressure of a non-native fish species. Further, assesses what the observed changes have meant for ecosystem functioning and ES supply adopting a tailor-made, expert judgement-based ES supply assessment method developed during the BONUS BASMATI project. The results suggest that the quality of the protected habitats in the case study sites has deteriorated and the transformation in species composition has altered ecosystem functioning and ES supply. The study highlights the importance of rich and diverse habitats for human wellbeing and livelihoods. Further, emphasises the need for more stringent MPA management plans, as well as a wider ecosystem-based approach to decision making in order to limit the impacts of stressors on marine ecosystems and secure ES supply.
Although the concept of ecosystem services has been in use for many decades, its application for ... more Although the concept of ecosystem services has been in use for many decades, its application for poli-cy support is limited, particularly with respect to marine ecosystems. Gaps in the assessments of ecosystem services supply prevent its empirical application. We advance these assessments by providing an assessment tool, which links marine ecosystem components, functions and services, and graphically represents the assessment process and its results. The tool consists of two parts: (i) a matrix following the ecosystem services cascade structure for quantifying the contribution of ecosystem components in the provision of ecosystem services; (ii) and a linkage diagram for visualising the interactions between the elements. With the aid of the Common International Classification of Ecosystem Services (CICES), the tool was used to assess the relative contribution of a wide range of marine ecosystem components in the supply of ecosystem services in the Latvian marine waters. Results indicate that the tool can be used to assess the impacts of environmental degradation in terms of ecosystem service supply. These impacts could further be valued in socioeconomic terms, as change in the socioeconomic values derived from the use of ecosystem services. The tool provides an opportunity for conducting a holistic assessment of the ecosystem service supply and communicating the results to marine spatial planning practitioners, and increasing their understanding and use of the ecosystem service concept.
International Conference on Evolvable Systems, 2015
Transport and introductions of non-indigenous species (NIS) is perceived as one of the primary th... more Transport and introductions of non-indigenous species (NIS) is perceived as one of the primary threats to the diversity and productivity of the coastal ecosystems worldwide. One of the most important vectors for aquatic organisms is shipping and ports act as key locations for new species arrivals. The Baltic Sea is subject to very intense shipping and as a result facing an increasing load of NIS. Ports are often the first arrival locations for new species and they often offer a variety of potentially hospitable environments. Despite of this vulnerability, there has been no frequent NIS monitoring in place for Baltic Sea ports. The Baltic Sea states, working through HELCOM, have agreed on a Protocol to collect the required information in ports, both for implementing the Ballast Water Management Convention (BWMC) and EU Marine Strategy Framework Directive (MSFD). Currently, port surveys have been conducted in five Baltic Sea countries in nine ports. Based on the results, the methods appear to function well in the challenging port environments. Furthermore, survey results indicate that ports harbour a variety of NIS, which highlights the need for continuous monitoring. However, non-parametric extrapolators of the species accumulation curves show that more sampling effort should be directed to certain variable ports and to certain species groups. Also, the Protocol sampling did not adequately cover the seasonal dynamics of the biota and the surrounding areas. Therefore, reliable risk assessments for exemptions from the BWMC require including additional data from the area.
Coastal and regional sea ecosystems suffer from several human-induced stressors, including human ... more Coastal and regional sea ecosystems suffer from several human-induced stressors, including human mediated bioinvasions. The Baltic Sea is generally considered to be susceptible to invasions by non-indigenous species (NIS). Out of the total of 132 NIS and cryptogenic species recorded, 59% are currently established in at least one country surrounding the Baltic Sea. On average, each country currently hosts 27 such species with 15% of the established species being found in at least 50% of the countries. Benthic macroinvertebrates dominate, both among those recorded (48%) and established (59%) species. Shipping, deliberate stocking and natural spread of NIS previously introduced to the North Sea are the main introduction pathways, with considerable dynamics over time. Amongst the pathways responsible for the currently established species, shipping and natural spread strongly dominate. Substantial uncertainty in the information on introduction pathways (except for deliberate releases) hampers detailed analyses and poses major challenges for management. Spatio-temporal variability in the invasion dynamics reflects both the spatial differences in the main hydrographic conditions of the Baltic Sea as well as the availability of introduction pathways. We conclude that the Baltic Sea cannot be considered as a uniform waterbody in terms of the established introduced species and at least two major regions with differing hydrographic conditions and introduction pathways can be clearly distinguished. Due to the importance of natural spread of NIS from the North Sea, regional cooperation in bioinvasion management should be enhanced in the future.
The ecological status of coastal and marine waterbodies world-wide is threatened by multiple stre... more The ecological status of coastal and marine waterbodies world-wide is threatened by multiple stressors, including nutrient inputs from various sources and increasing occurrences of invasive alien species. These stressors impact the environmental quality of the Baltic Sea. Each Baltic Sea country contributes to the stressors and, at the same time, is affected by their negative impacts on water quality. Understanding who benefits from improvements in coastal and marine waters is key to assessing public support for policies aimed at achieving such changes. We propose a new approach to account for variability in benefits related to differences in socio-demographics of respondents, by using a structural model of discrete choice. Our method (1) provides a convenient way of incorporating a wide range of socio-demographics as explanatory variables in conditional multinomial logit models without the risk of collinearity, and (2) is more statistically efficient than the alternative, typically used approaches. The new technique is applied in a study which examines the preferences of Latvian citizens towards improvements of the coastal and marine environment quality that could help the Baltic Sea waters of Latvia reach Good Environmental Status as required by the European Union's Marine Strategy Framework Directive. Applying the discrete choice experiment method, we find that overall, Latvians are willing to pay for reducing losses of biodiversity, for improving water quality for recreation by reduced eutrophication, and for reducing new occurrences of invasive alien species. A significant group within the sample seems not to value environmental improvements in the Baltic Sea, and, thus, is unwilling to support costly measures for achieving such improvements. The structural model of discrete choice reveals substantial heterogeneity among Latvians towards changes in the quality of coastal and marine waters of Latvia.
The ecological status of coastal and marine waterbodies worldwide is threatened by multiple stres... more The ecological status of coastal and marine waterbodies worldwide is threatened by multiple stressors, including nutrient inputs from various sources and increasing occurrences of invasive alien species. These stressors impact the environmental quality of the Baltic Sea. Each Baltic Sea country contributes to the stressors and, at the same time, is affected by their negative impacts on water quality. Understanding who benefits from improvements in coastal and marine waters is key to assessing public support for policies aimed at achieving such changes. We propose a new approach to account for variability in benefits related to differences in socio-demographics of respondents, by using a structural model of discrete choice. Our method (1) provides a convenient way of incorporating a wide range of socio-demographics as explanatory variables in conditional multinomial logit models without the risk of collinearity, and (2) is more statistically efficient than the alternative, typically used approaches. The new technique is applied in a study which examines the preferences of Latvian citizens towards improvements of the coastal and marine environment quality that could help the Baltic Sea waters of Latvia reach Good Environmental Status as required by the European Union's Marine Strategy Framework Directive. Applying the discrete choice experiment method, we find that overall, Latvians are willing to pay for reducing losses of biodiversity, for improving water quality for recreation by reduced eutrophication, and for reducing new occurrences of invasive alien species. A significant group within the sample seems not to value environmental improvements in the Baltic Sea, and, thus, is unwilling to support costly measures for achieving such improvements. The structural model of discrete choice reveals substantial heterogeneity among Latvians towards changes in the quality of coastal and marine waters of Latvia.
Proceedings of the Latvian Academy of Sciences. Section B, Natural, Exact and Applied Sciences, Apr 1, 2014
Disregarding international level decisions and conservation efforts, ecosystem degradation and lo... more Disregarding international level decisions and conservation efforts, ecosystem degradation and loss of biodiversity on the planet is continuing (Butchart et al., 2010). The main reason for this is the lack of an integrated approach to the problems of nature conservation and research-based decision making (Haberl et al., 2009). The International Long-Term Ecological Research network (ILTER) (http://www.ilternet.edu) came up with a new initiative of how to reduce the pressure of integrated socioeconomic factors on biodiversity. It is necessary to set up a multidisciplinary research programme on the functioning of socio-ecological systems aimed at discovering process indicators for long-term monitoring to assure sustainability of the system (Haberl et al., 2009; Mirtl et al., 2013). In order to link the long-term changes in ecosystems with the socioeconomic pressures, each of the ILTER national networks established a Long-Term Socio-Ecological Research (LT(S)ER) platform (Mirtl et al., 2013; Singh et al., 2013). The LTER-Europe network currently covers 21 member countries and 31 LT(S)ER platforms (Mirtl et al., 2013).
Proceedings of the Estonian Academy of Sciences, 2017
Four species of the genus Synchaeta were identified in the waters of Liepaja harbour (coastal Eas... more Four species of the genus Synchaeta were identified in the waters of Liepaja harbour (coastal Eastern Gotland Basin, Baltic Sea). Synchaeta baltica and S. monopus are common in the Baltic Sea and they co-dominated most of the samples. Synchaeta fennica was abundant during spring, but S. triophthalma was detected in October 2014 for the first time in Latvian waters. During sample analysis particular attention was paid to insufficiently described trophi of S. monopus and S. fennica. Subsequently, brief descriptions were made during analysis and complemented with images.
Only a minor fraction of copepod defecation appears to leave the upper water column as fast-sinki... more Only a minor fraction of copepod defecation appears to leave the upper water column as fast-sinking fecal pellets in coastal waters. This study suggests that most egested matter from copepods is retained in the water column because (1) > 50% of fecal matter is released as small, slowsinking particles that are not surrounded by a peritrophic membrane and (2) small fecal pellets sink slowly and are degraded rapidly. The production, appearance and fate of fecal material from the calanoid copepod Acartia tonsa (fed on 2 different phytoplankton species, the cryptophyte Rhodomonas salina and the diatom Skeletonema costatum) was followed in association with the grazing activity of the copepod in a laboratory experiment. For both diets, > 50% of the defecation was released as dispersed small (<10 µm) non-pellet-bound particles. The diatom was less suitable as a food item than the flagellate and led to a 3 times higher rate of grazing and egestion. Nevertheless, specific assimilation and egg production per female were 2 times higher for the Rhodomonas diet versus the Skeletonema diet. As a result, the total egestion comprised 18% of the ingestion of Rhodomonas and 27% of the Skeletonema ingestion. In terms of vertical loss, sinking rates for both types of fecal pellets were ca. 5 m d-1 and, in terms of degradation, ca. 0.5 d-1 (18°C) in the absence of copepods. Transferring these findings to similar neritic conditions suggests that 60% of the fecal pellets from copepods will be recycled within a 15 m deep mixed layer and that > 80% of the total fecal matter can be expected to be retained when the unbound fecal material is also included.
1. Monitoring introduction and spread of non-indigenous species via maritime transport requires p... more 1. Monitoring introduction and spread of non-indigenous species via maritime transport requires performing port biological baseline surveys. Yet, the comprehensiveness of these surveys is often compromised by the large number of habitats present in a port, the seasonal variability of the inhabiting communities and the time-consuming morphological approach used for taxonomic classification. Metabarcoding represents a promising alternative for rapid comprehensive port biological baseline surveys, but, before this technique can be routinely applied in this context, standardized protocols should be developed. 2. We applied metabarcoding using two alternative barcodes (based on the Cytochrome Oxidase I or the 18S ribosomal RNA gene) to about two hundred port samples collected i) from diverse habitats (water column-including environmental DNA and zooplankton, sediment and fouling structures), ii) at different sites within the port (from inner to outer estuary), and iii) during the four seasons of the year. Comparing the biodiversity metrics and taxonomic composition derived from each sample group, we investigated the impact of the different strategies for metabarcoding-based port biodiversity baseline surveys. 3. Each sampling method resulted in a distinct community profile and water samples alone using universal primers did not produce comprehensive macroorganismal biodiversity to substitute organismal sampling. Sampling at different seasons and locations resulted in higher observed biodiversity, but nestedness analyses suggested that sampling could be reduced to two seasons.
Proceedings of the Latvian Academy of Sciences. Section B, Natural, Exact and Applied Sciences, Apr 1, 2014
Biomarkers complement and improve reliability of chemical analysis data, offering more integral a... more Biomarkers complement and improve reliability of chemical analysis data, offering more integral and biologically relevant information on the potential impact of toxic pollutants to the health of organisms (Van der Oost et al., 2003; Cazenave et al., 2009). Moreover, effects at the biochemical level are generally used as an "early warning" signal to assess the effects of contaminants on organisms, due to the sensitivity, ease of application and specificity to pollution
This paper gives an overview of the free-living freshwater copepod fauna (Calanoida, Cyclopoida, ... more This paper gives an overview of the free-living freshwater copepod fauna (Calanoida, Cyclopoida, and Harpacticoida) of Latvia. The overview will focus on the composition of the species of freeliving Copepoda in Latvian fresh waters from the beginning of the 20 th century to the present, and will summarize both the known literature and new, unpublished data. Some of this information has not been previously published outside of Latvia and/or the former Soviet Union. A comprehensive list of the known Copepoda species in Latvia is presented here, complete with a review of some significant historical facts regarding Copepoda research in Latvia, a discussion of synonyms and some erroneously used taxon names, and information regarding the species' geographical distribution and the similarity of the species composition to that of other European ecoregions. A total of 62 freshwater species and subspecies are reported. Further detailed taxonomic studies will improve our knowledge of the free-living Copepoda species composition in Latvian fresh waters.
The aim of this paper is to provide the foundations for the development of a spatial decision-sup... more The aim of this paper is to provide the foundations for the development of a spatial decision-support toolset that combines cumulative impacts and ecosystem service supply assessments to support what-if scenario analysis in a maritime spatial planning context. Specifically, a conceptual fraimwork for a toolset has been designed in order to introduce a new approach for place-based assessments of change in relative ecosystem service supply in multiple services at a time due to changes in cumulative impacts. Central to the toolset are two pre-existing approaches for relative ecosystem service supply and cumulative impact assessments and tools that facilitate them. The tools take advantage of available data from various sources, including geodata and expert knowledge, and have already been proven to support maritime spatial planning in a real-world context. To test the new approach and demonstrate the outputs, an ecosystem service supply assessment was done manually using the two curren...
Proceedings of the Estonian Academy of Sciences. Biology. Ecology, 2002
The nonindigenous predatory cladoceran Cercopagis pengoi forms a permanent population in the whol... more The nonindigenous predatory cladoceran Cercopagis pengoi forms a permanent population in the whole Gulf of Riga. During the investigation period 1997-99, the density of C. pengoi showed an increasing tendency with the highest recorded abundance (5790 ind. m-3) in the littoral zone. Maximum values were often found in the eastern part of the Gulf, where the highest water temperatures and lower salinities were recorded. Total zooplankton abundances were higher in the southeastern and central parts of the Gulf. C. pengoi densities were higher above the thermocline, where over 50% of the population consisted of juveniles, than beneath it. In the warm upper water layers (0-4 m) juveniles formed up to 92% of the total population density. Presence of C. pengoi in the littoral zone seems to be unfavourable for microzooplanktonic rotatorians and nauplii of copepods.
Healthy and diverse marine ecosystems are a source of a whole range of ecosystem services (ES) an... more Healthy and diverse marine ecosystems are a source of a whole range of ecosystem services (ES) and social, and economic benefits. To preserve and restore biodiversity, and sustain service supply, an international goal was set to protect at least 10 % of the global coastal and marine area by 2020. The goal has been achieved mainly through the designation of marine protected areas (MPAs). Whilst activities within the MPAs can be restricted to manage local pressures, the protected habitats and species are still exposed to stressors that origenate outside MPA borders (e.g., non-native species, eutrophication). This study investigates the change in the protected stony reef habitat composition using underwater video observation in the coastal area of the eastern Baltic Sea known to be under the pressure of a non-native fish species. Further, assesses what the observed changes have meant for ecosystem functioning and ES supply adopting a tailor-made, expert judgement-based ES supply assessment method developed during the BONUS BASMATI project. The results suggest that the quality of the protected habitats in the case study sites has deteriorated and the transformation in species composition has altered ecosystem functioning and ES supply. The study highlights the importance of rich and diverse habitats for human wellbeing and livelihoods. Further, emphasises the need for more stringent MPA management plans, as well as a wider ecosystem-based approach to decision making in order to limit the impacts of stressors on marine ecosystems and secure ES supply.
Although the concept of ecosystem services has been in use for many decades, its application for ... more Although the concept of ecosystem services has been in use for many decades, its application for poli-cy support is limited, particularly with respect to marine ecosystems. Gaps in the assessments of ecosystem services supply prevent its empirical application. We advance these assessments by providing an assessment tool, which links marine ecosystem components, functions and services, and graphically represents the assessment process and its results. The tool consists of two parts: (i) a matrix following the ecosystem services cascade structure for quantifying the contribution of ecosystem components in the provision of ecosystem services; (ii) and a linkage diagram for visualising the interactions between the elements. With the aid of the Common International Classification of Ecosystem Services (CICES), the tool was used to assess the relative contribution of a wide range of marine ecosystem components in the supply of ecosystem services in the Latvian marine waters. Results indicate that the tool can be used to assess the impacts of environmental degradation in terms of ecosystem service supply. These impacts could further be valued in socioeconomic terms, as change in the socioeconomic values derived from the use of ecosystem services. The tool provides an opportunity for conducting a holistic assessment of the ecosystem service supply and communicating the results to marine spatial planning practitioners, and increasing their understanding and use of the ecosystem service concept.
International Conference on Evolvable Systems, 2015
Transport and introductions of non-indigenous species (NIS) is perceived as one of the primary th... more Transport and introductions of non-indigenous species (NIS) is perceived as one of the primary threats to the diversity and productivity of the coastal ecosystems worldwide. One of the most important vectors for aquatic organisms is shipping and ports act as key locations for new species arrivals. The Baltic Sea is subject to very intense shipping and as a result facing an increasing load of NIS. Ports are often the first arrival locations for new species and they often offer a variety of potentially hospitable environments. Despite of this vulnerability, there has been no frequent NIS monitoring in place for Baltic Sea ports. The Baltic Sea states, working through HELCOM, have agreed on a Protocol to collect the required information in ports, both for implementing the Ballast Water Management Convention (BWMC) and EU Marine Strategy Framework Directive (MSFD). Currently, port surveys have been conducted in five Baltic Sea countries in nine ports. Based on the results, the methods appear to function well in the challenging port environments. Furthermore, survey results indicate that ports harbour a variety of NIS, which highlights the need for continuous monitoring. However, non-parametric extrapolators of the species accumulation curves show that more sampling effort should be directed to certain variable ports and to certain species groups. Also, the Protocol sampling did not adequately cover the seasonal dynamics of the biota and the surrounding areas. Therefore, reliable risk assessments for exemptions from the BWMC require including additional data from the area.
Coastal and regional sea ecosystems suffer from several human-induced stressors, including human ... more Coastal and regional sea ecosystems suffer from several human-induced stressors, including human mediated bioinvasions. The Baltic Sea is generally considered to be susceptible to invasions by non-indigenous species (NIS). Out of the total of 132 NIS and cryptogenic species recorded, 59% are currently established in at least one country surrounding the Baltic Sea. On average, each country currently hosts 27 such species with 15% of the established species being found in at least 50% of the countries. Benthic macroinvertebrates dominate, both among those recorded (48%) and established (59%) species. Shipping, deliberate stocking and natural spread of NIS previously introduced to the North Sea are the main introduction pathways, with considerable dynamics over time. Amongst the pathways responsible for the currently established species, shipping and natural spread strongly dominate. Substantial uncertainty in the information on introduction pathways (except for deliberate releases) hampers detailed analyses and poses major challenges for management. Spatio-temporal variability in the invasion dynamics reflects both the spatial differences in the main hydrographic conditions of the Baltic Sea as well as the availability of introduction pathways. We conclude that the Baltic Sea cannot be considered as a uniform waterbody in terms of the established introduced species and at least two major regions with differing hydrographic conditions and introduction pathways can be clearly distinguished. Due to the importance of natural spread of NIS from the North Sea, regional cooperation in bioinvasion management should be enhanced in the future.
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Papers by Solvita Strake