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Climate change is expected to alter global temperature and precipitation patterns resulting in complex environmental impacts. The proposed higher precipitation in northern Scandinavia would increase runoff from land, hence increase the inflow of terrestrial dissolved organic matter (tDOM) in coastal regions. This could promote heterotrophic bacterial production and shift the food web structure, by favoring the microbial food web. The altered climate is also expected to affect transport and availability of organic micropollutants (MPs), with downstream effects on exposure and accumulation in biota. This study aimed to assess climate-induced changes in a Bothnian Sea food web structure as well as bioaccumulation patterns of MPs. We performed a mesocosms-study, focusing on aquatic food webs with fish as top predator. Alongside increased temperature, mesocosm treatments included tDOM and MP addition. The tDOM addition affected nutrient availability and boosted both phytoplankton and heterotrophic bacteria in our fairly shallow mesocosms. The increased tDOM further benefitted flagellates, ciliates and mesozooplankton, while the temperature increase and MP addition had minor effect on those organism groups. Temperature, on the other hand, had a negative impact on fish growth and survival, whereas tDOM and MP addition only had minor impact on fish. Moreover, there were indications that bioaccumulation of MPs in fish either increased with tDOM addition or decreased at higher temperatures. If there was an impact on bioaccumulation, moderately lipophilic MPs (log Kow 3.6 - 4.6) were generally affected by tDOM addition and more lipophilic MPs (log Kow 3.8 to 6.4) were generally affected by increased temperature. This study suggest that both increased temperatures and addition of tDOM likely will affect bioaccumulation patterns of MPs in shallow coastal regions, albeit with counteracting effects.

Climate change has been projected to cause increased temperature and amplified inflows of terrestrial organic matter to coastal areas in northern Europe. Consequently, changes at the base of the food web favoring heterotrophic bacteria over phytoplankton are expected, affecting the food web structure. We tested this hypothesis using an outdoor shallow mesocosm system in the northern Baltic Sea in early summer, where the effects of increased temperature (+ 3°C) and terrestrial matter inputs were studied following the system dynamics and conducting grazing experiments. Juvenile perch constituted the highest trophic level in the system, which exerted strong predation on the zooplankton community. Perch subsequently released the microbial food web from heavy grazing by mesozooplankton. Addition of terrestrial matter had a stronger effect on the microbial food web than the temperature increase, because terrestrial organic matter and accompanying nutrients promoted both heterotrophic bacterial production and phytoplankton primary production. Moreover, due to the shallow water column in the experiment, terrestrial matter addition did not reduce the light below the photosynthesis saturation level, and in these conditions, the net-autotrophy was strengthened by terrestrial matter enrichment. In combination with elevated temperature, the terrestrial matter addition effects were intensified, further shifting the size distribution of the microbial food web base from picoplankton to microphytoplankton. These changes up the food web led to increase in the biomass and proportion of large-sized ciliates (>60 µm) and rotifers. Despite the shifts in the microbial food web size structure, grazing experiments suggested that the pathway from picoplankton to nano- and microzooplankton constituted the major energy flow in all treatments. The study implies that the microbial food web compartments in shallow coastal waters will adjust to climate induced increased inputs of terrestrial ma

Phytoplankton are used worldwide to monitor environmental status in aquatic systems. Long-time series of microscopy-analyzed phytoplankton are available from many monitoring stations. The microscopy-method is however time consuming and has short-comings. DNA metabarcoding has been suggested as an alternative method, but the consistency between different methods need further investigation. We performed a comparative study of microscopy and metabarcoding analyzing micro- and nanophytoplankton. For metabarcoding, 25-1000 ml seawater were filtered, DNA extracted and the 18S and 16S rRNA gene amplicons sequenced. For microscopy, based on the Utermöhl method we evaluated the use of three metrics: abundance, biovolume and carbon biomass. At the genus, species, and unidentified taxa level, metabarcoding generally showed higher taxonomic diversity than microscopy, and diversity was already captured at the lowest filtration volume tested, 25 ml. Metabarcoding and microscopy displayed relatively similar distribution pattern at the group level. The results showed that the relative abundances of the 18S rRNA amplicon at the group level best fitted the microscopy carbon biomass metric. The results are promising for implementing DNA metabarcoding as a complement to microscopy in phytoplankton monitoring, especially if databases would be improved and group level indexes could be applied to classify the environmental state of water bodies., Originally included in thesis in manuscript form.

The field of educational leadership research has been predominantly focused on school leadership. However, despite the distinctive characteristics of early childhood education, there is limited understanding of educational leadership at this level. Moreover, leadership has been conventionally studied from a traditional masculine perspective, despite the emergence of research literature in issues of female leadership. In this context, the study reported here sought to investigate, from a gender perspective, everyday practices of kindergarten-level headteachers and level coordinators in schools. This qualitative study is based on 24 in-depth interviews with early childhood education headteachers and school level coordinators. In addition, a job shadowing-based technique was carried out to follow the work of six participants over a working week, followed by closing interviews. The results of the study suggest that a leadership of well-being prevails among the participants, which is consistent with their professional ethics. Although this style can enhance their professional identity, from a gender perspective the research outcomes illustrate that this style has a double-edged dimension. The authors warn against the risk of uncritically praising “female leadership” and illustrate the tensions that can arise from perpetuating gender stereotypes. From an ethic of feminist care, the paper concludes proposing challenges in this field of educational leadership., La investigación en el campo del liderazgo educativo ha predominado en la literatura escolar, mientras existe escaso conocimiento al respecto en la educación inicial, a pesar de las distinciones de este nivel. A su vez, el liderazgo se ha estudiado desde una perspectiva tradicionalmente masculina, aunque existe una incipiente literatura en el área del liderazgo femenino. En este contexto, la investigación indaga, desde una perspectiva de género, las visiones y prácticas que ejercen las directoras de jardines infantiles y coordinadoras del nivel en establecimientos escolares. Con el fin de lograr este objetivo se realizó un estudio cualitativo basado en entrevistas en profundidad a 24 directoras/coordinadoras de establecimientos de distintas dependencias y un seguimiento a seis de las entrevistadas a través de un enfoque etnográfico durante la jornada laboral de una semana, a lo que se sumó entrevistas de cierre a las mismas seis directoras/coordinadoras. Los resultados del estudio evidencian que prevalece un liderazgo del bienestar de parte de las agentes directivas, lo que es consistente con su ética profesional en el trabajo con la primera infancia. Aunque este estilo pueda traer beneficios para su identidad profesional, desde una perspectiva de género la investigación da cuenta de que tal tipo de liderazgo implica a su vez un doble filo. Las autoras alertan el riesgo de elogiar de modo acrítico un “liderazgo femenino” y evidencian tensiones al perpetuar estereotipos de género. El texto finaliza proponiendo nuevos desafíos al respecto, desde una ética del cuidado feminista.