Restoration of endangered epiphytic lichens in fragmented forest landscapes

In a situation with increasingly rapid changes in landscape mosaics, driven by large-scale forestry and future climate change, a number of epiphytic lichens are now becoming threatened. Many of these species are limited either by dispersal or the subsequent processes of immobilisation on the substrate and germination. Overcoming the bottleneck of dispersal and/or reproduction may therefore constitute a key factor in species conservation. The main aim of this thesis is to evaluate different strategies to optimise efficiency in restoration of populations of endangered epiphytic lichens in fragmented forest landscapes, with a special emphasis on the importance of habitat quality and transplantation techniques. The thesis includes the development of a modeling tool for habitat evaluation in relation to photosynthetic performance of individual species (III); exploration of underlying causes for habitat restrictions in hydrophilic lichens (IV); and identification of habitat and substrate characteristics that 1) are associated with high vitality in natural populations of hydrophilic lichens (II), 2) are beneficial for establishment during active transplantation of thallus fragments (I) or isidia (V), and 3) are beneficial for photosynthetic activity in adult thalli (III, IV). The occurrence of pronounced photosynthetic activation time lags among hydrophilic species, with full activity for some species being reached first 24 h after hydration, is reported for the first time in the present study and may be one of the physiological causes explaining habitat restrictions in rare hydrophilic lichens (IV). Using a dynamic water and activity model, we assessed the capacities of four hydrophilic (Bryoria bicolor, Lobaria amplissima, Platismatia norvegica and Usnea longissima) and a generalist species (Platismatia glauca) to rehydrate and activate photosynthesis by liquid water and humid air available in natural habitats (III). Simulations show that for three of the four studied hydrophilic species, species-specific PSII activation time lags can, in combination with microclimatic differences, control photosynthetic performance in a most dramatic manner (III, IV). The distribution patterns of hydrophilic lichens coincide very well with habitat features that generate high realised activity among the slowly activated species studied here (II, III, IV). Both close proximity to streams and the presence of turbulent water had a consistent strong positive impact on realised activity among the studied species (IV). The occurrence of activation time lags may explain both the higher abundances in oceanic core habitats, and the affinity for stream habitats and turbulent water displayed by marginal populations of suboceanic lichens such as P. norvegica (II). Further, we have shown that transplantations of fragments (using Evernia divaricata and Ramalina dilacerata) or isidia (using P. norvegica) can constitute a valuable tool for restoration of endangered lichen populations, and that both habitat characteristics (I) and the mode of transplantation (I, V) is of vital importance to fragment vitality. In Paper V, where isidia of P. norvegica were transplanted into six sites in the regions of Jämtland and Trøndelag in Central Scandinavia, we have shown that preparation of transplant surfaces with an adhesive Ac-Di-Sol® solution may constitute a highly efficient tool for enhancing the outcome of restorative transplantations targeting epiphytic lichens (V). However, in order to enhance the possibilities for long-term viability and persistence of the population, it is essential that restoration efforts are concentrated to habitats and substrates that can be viewed as optimal for the species in question (I-V). The model developed in Paper III and used in Paper IV may provide a tool for identifying such suitable habitats. Further, this thesis highlights the importance of fringe populations for conservation of endangered suboceanic lichens in Scandinavia (II), and also underscores the importance of separating the processes of dispersal, immobilisation and establishment, when studying lichen distributional patterns (I, II, V)

Why do some local authorities have such poor websites? Insights from Sweden

Some Swedish local authorities have embraced online services and forms of digital democracy. Others have been slow to take up the opportunity. Gustav Lidén rates the country’s 290 municipalities according to the depth of their digital engagement, and looks at the possible factors influencing it. Lack of enthusiasm from senior politicians and bureaucratic inertia are key reasons why local councils are reluctant to invest in digital politics

Renewable energy from wastewater grown microalgae - a concept for nutrient recycling and sustainable energy recovery

Wastewater is an excellent source of nutrients and energy. By treating the wastewater in a clever way, it is possible to both recycle nutrients and recover energy, and thereby create opportunities for a sustainable system. In conventional wastewater treatment where the activated sludge process is used, aeration is needed and a lot of biomass is produced. In regions with warmer climate, or if low-valuable heat is available for heating this technique could be replaced with an anaerobic one. With anaerobic techniques, less sludge is produced, the need for aeration is decreased and potentially more energy can be recovered. An increased interest in renewable energy sources has put demand on finding suitable substrates for production of biobased fuels. For this purpose, algal biomass presents interesting characteristics. Algae use sunlight, carbon dioxide and nutrients for growth. One of the hurdles with production of algal biomass is nutrient supply but this can be solved by growing algae in wastewater. In this way two problems are solved: the algae are supplied with nutrients at the same time as nutrient reduction in the wastewater is accomplished. In this study, the feasibility of integrating an algal step in a wastewater treatment system was evaluated based on a series of laboratory experiments. Further, a concept for wastewater treatment including an Anaerobic Moving Bed Biofilm Reactor (AnMBBR) and algal cultivation was compared to an existing wastewater treatment plant (WWTP). Nutrient reduction over the algal cultivation showed more than 97% reduction of phosphate and more than 84% reduction of ammonium. Algal harvesting experiments showed that it was possible to efficiently separate algal biomass and treated water by sedimentation for 30 minutes after flocculation by addition of ferric chloride and cationic polymer. These experiments also showed that it was possible to meet the discharge limits for P-tot (0.3 mg/L), N-tot (10 mg/L) and COD (70 mg/L). Harvesting efficiency of up to 96% was achieved. Methane potential from primary sludge was found to be 295 NmL/gCOD and for untreated microalgae, dominated by Scenedesmus sp., 95-108 NmL/gCOD. In batch tests, no synergistic effects could be seen for co-digestion of algae and primary sludge. The methane yield for algal biomass was increased by 46% when pretreated at 120°C for 30 minutes and by 74% when pretreated at 170°C for 30 minutes. Evaluation of the proposed concept showed that the ratio between primary sludge and algae would be 32:68 on volatile suspended solids basis, if algae are grown 12 months per year. Compared to a conventional WWTP which uses the activated sludge process, the yield of methane was 35% higher without pretreatment, and up to 75% higher if pretreatment is applied. Finally, it was found that microalgae have a great potential for biogas production compared to some energy crops. The energy potential of algae was found to be 60-160 MWh/(ha year) depending on pretreatment and cultivation period (8-12 months/year).I dagens samhälle används stora mängder vatten som måste renas innan det släpps tillbaka ut i naturen. Rening av vattnet sker i avloppsreningsverk som ska minska mängden organiskt material och mängden näringsämnen i vattnet innan det släpps ut. Om vattnet inte renas finns det en risk för negativ påverkan på sjöar och vattendrag, t.ex. övergödning. Fosfor är ett av de näringsämnen som finns i avloppsvatten och som ofta behöver tillsättas som gödsel i jordbruk. Genom att återvinna fosforn som finns i avloppsvatten minskar belastningen på jordklotets ändliga fosforreserver. En annan vinst med att återvinna näringsämnen från avloppsvatten är att energiförbrukningen kan minska. Vanligtvis fixeras kväve från luften, i en energikrävande process, för att användas som gödningsmedel. Om kvävet i avloppsvattnet istället används minskar energiförbrukningen. Eftersom efterfrågan på förnybara energikällor ökar, krävs det nya system för att möta efterfrågan. Genom att betrakta avloppsvatten som en resurs finns det positiva vinster att göra. Det organiska materialet i avloppsvattnet kan omvandlas till biogas genom att det behandlas i syrefri miljö. Biogasen kan användas för att generera el och värme eller som fordonsbränsle. I konventionell avloppsvattenrening används ofta ett luftat steg där mycket av energin går förlorad. Genom att byta ut detta steg mot ett syrefritt kan mer av energin tas tillvara. Detta är möjligt i lite varmare klimat, eller om spillvärme finns tillgänglig för uppvärmning. Vidare har det även föreslagits att biobaserade bränslen, t.ex. biogas kan produceras från mikroalger. Mikroalger är mikroskopiskt små organismer som på samma sätt som växter utnyttjar fotosyntesen. Det betyder att de med hjälp av solljus kan omvandla koldioxid och vatten till kolhydrater. Förutom koldioxid och solljus behöver algerna näringsämnen såsom kväve och fosfor. Ett problem har varit att på ett hållbart sätt förse algerna med tillräckliga mängder näringsämnen. Därför har det föreslagits att alger kan odlas i avloppsvatten. På detta sätt uppnås två mål samtidigt; vattnet renas och algerna förses med den näring de behöver. När algerna tagit upp näringsämnena från avloppsvattnet, separeras algbiomassan och används för biogasproduktion. Vattnet har blivit renat och kan släppas ut utan att påverka den omgivande naturen negativt. Biogasprocessen kallas även rötning. Det som blir kvar efter att det organiska materialet omvandlats till biogas kallas rötrest. Rötresten innehåller de näringsämnen som fanns i materialet från början. Detta betyder att det går att skapa ett kretslopp om alger används för näringsreduktion i avloppsvattenrening. Algerna tar upp näringen från vattnet när de växer. När algerna sedan rötas omvandlas den organiska delen av algerna till biogas och näringsämnena stannar kvar i rötresten. Rötresten kan användas som gödningsmedel och biogasen kan användas till el- och värmeproduktion eller som fordonsbränsle. När biogasen förbränns avges koldioxid men eftersom algerna tar upp koldioxid när de växer, fås även ett kretslopp för kol. För att öka tillväxten hos algerna kan extra koldioxid tillsättas i odlingen. Syftet med detta examensarbete var att undersöka om det går att rena avloppsvatten med hjälp av mikroalger och sedan använda mikroalgerna för produktion av biogas. Den experimentella delen av arbetet fokuserade på hur algerna kan separeras från vattnet, hur mycket biogas som kan produceras och hur värmebehandling av algerna påverkar hur mycket biogas som bildas. Resultaten ledde fram till en jämförelse mellan ett befintligt avloppsreningsverk och en möjlig ny design. Resultaten visade att tillräckligt hög reningsgrad gick att uppnå med hjälp av alger och att den totala mängden biogas som kunde utvinnas var högre än vid det befintliga verket som användes vid jämförelsen. Det visade sig också att det gick att utvinna mer biogas genom att värmebehandla algerna. Även om vidare utredningar behövs så verkar avloppsvattenrening med hjälp av mikroalger och biogasproduktion från algerna vara ett mycket lovande koncept

Safe drinking water in a changing environment : Membrane filtration in a Swedish context

Surface water is vital for Swedish drinking water supply. In the past decades, a trend of increased total organic carbon (TOC) concentrations has led to higher consumption of coagulants in drinking water treatment, and has pushed the levels in the outgoing water closer to the allowed levels of TOC. Also, two occasions of cryptosporidium outbreaks in northern Sweden have stressed the importance of reliable microbiological barriers.Ultrafilters and tighter membranes can, due to size exclusion, produce a safe water by reducing the occurrence of parasites, bacteria and virus 10,000-fold or more. Combined with a coagulation pretreatment, ultrafiltration has the additional benefit of removing natural organic matter (NOM), whereas nanofiltration can remove NOM without coagulant. This dissertation presents results for NOM removal by ultrafiltration and nanofiltration from several raw water sources. The results were collected in mobile pilot plants at several locations. The coagulation and ultrafiltration process could achieve similar NOM removal as current chemical treatment, to a similar cost, and with a lower environmental impact. Hollow fiber nanofiltration achieved advanced NOM removal, reducing TOC with around 90 % and UV-absorbing species at 254 nm of up to 97 %. Thus, it is selective to aromatic NOM, similar to conventional treatment. The cost for the operation of a treatment process would increase if coagulation/sedimentation would be replaced with a nanofiltration step, but the environmental impact would decrease substantially. The NOM removal was studied by the aid of fluorescence spectrometry. Fluorescence can be related to characteristics of NOM, which has been implemented in this study. The application of fluorescence as a monitoring method has been evaluated through indices and other fluorescence derived parameters. Some of these, e.g. fluorescence index, have showed significant correlations to treatment efficiencies. Similar to TOC and UV-absorbance, significant changes in the nanofilter permeate was possible to relate to integrity breaches, and these NOM related parameters have shown potential for integrity monitoring.With such advanced NOM removal and advanced monitoring techniques, membrane filtration has a promising future in Swedish drinking water treatment. It decreases the risk for waterborne pathogens. Specifically, nanofiltration can lead to lower risks for disinfection by-products and regrowth in the distribution system

Sobre la presencia de Fumaria melillaica Pugsley (Papaveraceae) en Murcia (España)

Se cita por primera vez para Murcia Fumaria melillaica Pugsley. Se presenta una ilustración y un mapa revisado

“Blood, Bucks and Bias”: Reliability and biasability of crime scene investigators’ selection and prioritization of blood traces

When crime scene investigators (CSIs) encounter crime scenes with large volumes of blood, some selection and prioritization is often needed, and this will impact on what blood is and is not available for forensic analysis. What factors influence CSIs decision making process is largely unknown. This study examines the effects of awareness of limited resources and irrelevant contextual case information indicating either a homicide or a suicide on CSIs collection of blood traces. To this end, two scenario-based experiments with CSIs and novices were conducted. Overall, the results suggest that even when CSIs decisions are made under identical conditions, their trace selection varies both when it comes to numbers and locations. Furthermore, awareness of limited resources made CSIs collect fewer traces and their selections also varied following the contextual case information, showing similarities and differences with novices. Since blood traces can be used to establish both activity and identity the findings can have important implications for the subsequent investigation as well as trial

Evidence from Sweden: how local governments shape migration policies

While migration policies are typically set by national governments, local governments play a key role in managing the settlement of migrants and their integration into society. Based on an analysis of Swedish migration policy in the aftermath of the 2015-16 migration crisis, Jon Nyhlén and Gustav Lidén shed light on the significance of the local level of government for migration policy

Strategic factors supporting improved profitability.

Background: A common indicator of company long time survival and performance is its profitability. What then lies behind a company’s profits is a popular field of study, although more prescriptive than inquisitive literature has been published. One of the main reasons is that identification of what has led to an increase in profitability is extremely complex, as companies work in different micro and macro environments and that these change over time. Studies are usually performed in retrospective, and what was applicable to one company at one time, might not be so to a different company at a different time and in a different environment. Few studies have been conducted summing up the current knowledge base within the field of Strategic Management in an accessible manner. Purpose: The purpose of this thesis was to identify strategic factors in companies that had improved their profitability and evaluate their impact and difficulty to change, combining them into a theoretical framework displaying their perceived relative importance in a presentation possible to use as a foundation for a more practically useful model. Method: Qualitative studies of Strategic management literature, both of an academic and popular nature. Identification of relevant sources was done mainly through meta-studies. Sources and findings were summarised and analysed, with regard to concepts and their connections. Conclusions: Through study Strategic Management literature, 13 concepts, split into four main categories were singled out as being most important in affecting profitability. The categories and respective concepts are: Current operation – Control measures, Evaluation, Rewards and Motivation Organization – Focus on competencies and Strategic organisation Foundation – Culture, Purpose, Communication and Leadership Forward operation – Flexibility, Creativity and Learning Furthermore it was concluded that in-between the many sources studied, there was no major contradictory ideas found. Some contradictory views of academics and practitioners brought value to the end result