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  • 101.
    Pires, Mateus Marques
    et al.
    Ecology and Evolution Laboratory, Vale do Taquari University (UNIVATES), Lajeado, Rio Grande Do Sul, Brazil.
    Périco, Eduardo
    Ecology and Evolution Laboratory, Vale do Taquari University (UNIVATES), Lajeado, Rio Grande Do Sul, Brazil.
    Renner, Samuel
    Ecology and Evolution Laboratory, Vale do Taquari University (UNIVATES), Lajeado, Rio Grande Do Sul, Brazil.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Predicting the effects of future climate change on the distribution of an endemic damselfly (Odonata, Coenagrionidae) in subtropical South American grasslands2018In: Journal of Insect Conservation, ISSN 1366-638X, E-ISSN 1572-9753, Vol. 22, no 2, p. 303-319Article in journal (Refereed)
    Abstract [en]

    Climate change is predicted to affect the distribution of freshwater taxa, and stronger impacts are expected on endemic species. However, the effects of future climates on freshwater insects from the Neotropical region have been generally overlooked. In this study, the distribution of a damselfly (Cyanallagma bonariense, Odonata, Coenagrionidae) endemic to the subtropical South American grasslands (Pampa) was modelled in relation to future scenarios of high greenhouse gas emissions (RCP 8.5) for 2050 and 2070. For this purpose, ecological niche models were developed based on assumptions of limited dispersal and niche conservatism, and the projected distribution of C. bonariense was contrasted with the location of current protected areas (PAs) in the Pampa. A broad potential distribution of C. bonariense was indicated throughout the Pampa, and projections predicted a predominance of range contractions rather than range shifts in climatically suitable areas for C. bonariense in 2050 and 2070. Projections of suitable areas overlapped in central Argentina and southernmost Uruguay in these periods. Our results indicated a potential resilience of C. bonariense to future climate change, which is likely related to the low restrictions in habitat use of C. bonariense. In every projection, however, most PAs were expected to lose effectiveness, as by 2070 most PAs fall outside the range of the predicted distribution of C. bonariense. Thus, the creation or enlargement of PAs in these areas is recommended and these results represent an important information for the conservation of endemic freshwater insects under global warming scenarios in an overlooked Neotropical landscape. © Springer International Publishing AG, part of Springer Nature 2018

  • 102.
    Pitkänen, Kim
    Halmstad University, School of Humanities (HUM).
    Ekologiskt Hållbar Turism: En nisch för naturens bästa2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Det är allmänt känt att turismen för med sig negativa ekologiska konsekvenser och har gjort det sedan charterturismen på allvar slog igenom under -50 och 60-talet. På senare tid har alternativ turism börjat gro och tagit sig upp. Att massturismen är dominerande råder det inga tvivel om men det är viktigt att alternativ turism såsom ekoturism ser dagens solljus, en nisch i turismen som ska vara ekologiskt hållbar.

    Vandringen mot toppen är lång och brant för den ekologiskt hållbara turismen, nyligen har den börjat se dagsljuset men massturismen tar åt sig nästan all energi från solljuset. Det innebär att den ekologiskt hållbara turismen måste kämpa i hård konkurrens med de andra aktörerna på marknaden. Aktörer som i dagsläget och även i fortsättningen kommer vara starkare, men det säger inte att det inte finns plats för ekologiskt hållbar turism.

    Uppsatsen visar att det finns ett bra utbud av litteratur om ekoturism som tar upp både skrämmande exempel där varumärket utnyttjats till skadligare verksamhet och exempel med rätt använd ekoturism som ett verktyg för värnande av biologisk mångfald. Den litterära granskningen redogör för betydelsen av ekologiskt hållbar turism och vad som kan göras för att nå dit.

    En enkätundersökning gjordes i sydvästra Sverige med syfte att ta reda på hur folket ser på ekologiskt hållbar turism. Vissa intressanta skillnader fanns mellan personer av samma kön och kvinnor gentemot män, men glädjande var att de flesta av dem 136 svarande trodde eller hoppades att den ekologiskt hållbara turismen har en ljus framtid att gå till mötes. I Sverige har vi idag 81 av Naturens Bästa godkända ekoturistarrangörer. Trots skuggan från de större verksamheterna verkar det finnas tillräckligt med ljus och plats för den ekologiskt hållbar turismen att slå sig in på marknaden.

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    fulltext
  • 103.
    Pålsson, Joakim
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Ecology and Environmental Science.
    Geografisk spridning och morfologisk variation hos Brachygaster minutus (Hymenoptera: Evaniidae) i Sverige2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 104.
    Renner, Samuel
    et al.
    Ecologia e Sensoriamento Remoto, Centro Universitário Univates, Lajeado-RS, Brazil.
    Perico, Eduardo
    Ecologia e Sensoriamento Remoto, Centro Universitário Univates, Lajeado-RS, Brazil.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Dragonflies (Odonata) in Subtropical Atlantic Forest fragments in Rio Grande do Sul, Brazil: seasonal diversity and composition2013In: Scientia Plena, ISSN 1808-2793, Vol. 9, no 1, article id 012401Article in journal (Other academic)
    Abstract [en]

    One of the most endangered ecosystems in America is the Atlantic Forest, which demands emergency actions to protect its remnants as well its biodiversity. In this situation the species inventory can develop a management role for the future, determining specific areas that should be preserved as well the species composition and richness can be used as an indicator of a healthy ecosystem. The use of dragonfly species composition has proven its potential indication of quality habitats. The Odonata species actually still poorly known in the Neotropical region and has never been used as a tool to analyze the actual conditions of aquatic environments particularly in the Subtropical Atlantic Forest, which occurs in south of Brazil. A systematic survey was carried out in aquatic systems located at remnants of forest from March 2011 to February 2012. A total of 565 specimens belonging to 34 species, distributed in 5 families were sampled. Libellulidae was dominant, with 14 species, followed by Coenagrionidae, Gomphidae, Lestidae and Aeshnidae. Through inventory survey we deepen the Odonata composition knowledge and performed a statistic analysis.

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    Dragonflies
  • 105.
    Renner, Samuel
    et al.
    Laboratório de Ecologia e Evolução, Universidade do Vale do Taquari – Univates, Lajeado, Brazil.
    Périco, Eduardo
    Laboratório de Ecologia e Evolução, Universidade do Vale do Taquari – Univates, Lajeado, Brazil.
    Dalzochio, Marina S.
    Laboratório de Ecologia e Evolução, Universidade do Vale do Taquari – Univates, Lajeado, Brazil.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Ecoregions within the Brazilian Pampa biome reflected in Odonata species assemblies2019In: Austral ecology (Print), ISSN 1442-9985, E-ISSN 1442-9993, Vol. 44, no 3, p. 461-472Article in journal (Refereed)
    Abstract [en]

    Based on vegetation composition, previous studies of the Pampa biome in southern Brazil have defined seven ecoregions within the area. Here, we test this ecoregion approach studying the semi-aquatic insect group Odonata in five of these regions, aiming at comparing the ecoregions to the more traditional environmental predictors of water quality and land cover. Based on a data set of occupancy comprising 99 species distributed between 131 localities, a one-way Permutational Multivariate Analysis of Variance was used to compare differences in the species composition between the ecoregions, followed by a Principal Component Analysis to visualize the variation. The composition varied significantly between all groups tested, and the ordination explained 61.8% of the variance. A partial redundancy analysis of ecoregions, land cover and water quality variables explained 71% of the variance in Odonata community structure. Ecoregion was the most important predictor, followed by water quality and land cover. Within these species assemblies, we could select certain species that were representative of a given ecoregion, to which their distribution within the Pampa biome was entirely or mainly confined. Of 24 representative species 41.7% were rare, while the rest were more abundant and, hence, easier to detect. We suspect that the differences found between the Pampa ecoregions might be due to geology, as such factors may be strong determinants of biodiversity. Specific ecological requirements at the family and genus levels also seemed to act selectively on the species compositions within the ecoregions. Today, the Pampa is highly fragmented due to agricultural activities such as rice cultivation, extensive cattle farming and forest plantations. We suggest that an ecoregion-based approach to the implementation of conservation measures may be the best way to help these distinct species assemblies survive. © 2018 Ecological Society of Australia

  • 106.
    Renner, Samuel
    et al.
    Universidade do Vale do Taquari, Bairro Universitário, Lajeado, RS, Brazil.
    Périco, Eduardo
    Universidade do Vale do Taquari, Bairro Universitário, Lajeado, RS, Brazil.
    Ely, Gerson
    Universidade do Vale do Taquari, Bairro Universitário, Lajeado, RS, Brazil.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Preliminary dragonfly (Odonata) species list from the Pampa biome in Rio Grande do Sul, Brazil, with ecological notes for 19 new records for the state2017In: Biota Neotropica, ISSN 1806-129X, E-ISSN 1676-0611, Vol. 17, no 4, article id e20170374Article in journal (Refereed)
    Abstract [en]

    An inventory of Odonata was carried out in the southern half of the state of Rio Grande do Sul, Brazil, in the Pampa biome. Originally, this biogeographical region was covered mostly by open fields and grassland, with sections of higher vegetation surrounding water bodies and rocky hills. Today the landscape is fragmented due to agricultural activities, mainly cattle farming, rice crops and forest plantations. Our survey was conducted in three municipalities from this region, between March 2015 and April 2016. Aiming at a general overview of the species composition, our sampling sites were selected on a wide basis, including lakes, bogs, temporary water bodies, small streams and river sections. Eighty two species of Odonata were collected comprising 40 genera and seven families. The dominant families were Libellulidae (56,1%), Coenagrionidae (24,5%) and Aeshnidae (7,3%). We found a diverse odonate assemblage, adding 19 new species records for the state of Rio Grande do Sul.

  • 107.
    Renner, Samuel
    et al.
    Lab de Evolução e Ecologia, Centro Universitário Univates, Lajeado, RS, Brazil.
    Périco, Eduardo
    Lab de Evolução e Ecologia, Centro Universitário Univates, Lajeado, RS, Brazil.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Effects of exotic tree plantations on the richness of dragonflies (Odonata) in Atlantic Forest, Rio Grande do Sul, Brazil2016In: International Journal of Odonatology, ISSN 1388-7890, Vol. 19, no 4, p. 207-219Article in journal (Refereed)
    Abstract [en]

    One of the forest types occurring in Southern Brazil is the mixed ombrophilous forest (MOF), a subtype of the Atlantic Forest, which is one of the richest biomes on Earth. This biome currently remains as a highly fragmented mosaic, under pressure from human development. The diversity and ecology of most animal groups in this biome are poorly known. We studied Odonata in a large forest fragment, including an ecological reserve: the Floresta Nacional de São Francisco de Paula (FLONA-SFP), in Rio Grande do Sul, administrated by the Brazilian government. The reserve is dominated by MOF with sectors of Pinus elliottii and Araucaria angustifolia. Three surveys of these forest sectors over one year yielded 42 species, with the highest species richness recorded in the P. elliottii sector. The odonate species recorded here are all generalist in terms of habitat preferences, but they appeared only in low numbers and were very particular in their occurrence pattern. We therefore assume that the introduction of an alien element in the Atlantic Forest has given rise to a new species assemblage, where the ecology of the species is adapted to the novel habitat of Pinus plantations. As expected, the species occurring in the MOF sectors were mainly habitat specialists. The Araucaria plantations had an intermediate species composition. Despite the differences observed in habitat preference between generalist and specialist species, such exotic plantation habitats may act as a temporary biodiversity reservoir for further habitat colonization. © 2016 Worldwide Dragonfly Association

  • 108.
    Renner, Samuel
    et al.
    Centro Universitário Univates, Lajeado, RS, Brazil.
    Périco, Eduardo
    Centro Universitário Univates, Lajeado, RS, Brazil.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    List of Odonates from the Floresta Nacional de São Francisco de Paula (FLONA - SFP), with two new distribution records for Rio Grande do Sul, Brazil2016In: Biota Neotropica, ISSN 1806-129X, E-ISSN 1676-0611, Vol. 3, article id e20150132Article in journal (Refereed)
    Abstract [en]

    A survey of Odonata was carried out in the National Forest FLONA - SFP, Northeastern region of the Rio Grande do Sul state, Brazil. This conservation unit is mainly covered by Mixed Ombrophilous Forest (MOF), a subtype of Atlantic Forest biome, being also areas covered in planted Pinus, planted Araucaria and open fields. Our sampling efforts were conducted in thirty aquatic environments inside this reserve during the period between January 2014 and November 2014. The sampling sites were selected randomly, comprehending lakes, bogs, small streams and river sections, all inserted in the four vegetation types occurring in the reserve. Fortysix species of Odonata were collected and grouped into 23 genera and seven families. The dominant families were Coenagrionidae (32%), Libellulidae (32%), Aeshnidae (12%), and, Calopterygidae and Lestidae (9%). As expected, the findings revealed the presence of a highly diverse Odonate assemblage, mainly represented by generalist species in the most human disturbed sectors (Pinus and Open fields) and some specialist species in the pristine forest. Two species were registered for the first time in the state of Rio Grande do Sul, Brazil: Libellula herculea Karsch, 1889 (Libellulidae) and Heteragrion luizfelipei Machado, 2006 (Heteragrionidae). © 2016, Universidade Estadual de Campinas UNICAMP. All rights reserved.

  • 109.
    Renner, Samuel
    et al.
    Ecologia e Sensoriamento Remoto, Centro Universitário Univates, Lajeado-RS, Brasil.
    Périco, Eduardo
    Ecologia e Sensoriamento Remoto, Centro Universitário Univates, Lajeado-RS, Brasil.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Man-made lakes form species-rich dragonfly communities in the Brazilian Atlantic Forest (Odonata)2016In: Odonatologica, ISSN 0375-0183, Vol. 45, no 3-4, p. 135-154Article in journal (Refereed)
    Abstract [en]

    One of the forest types occurring in Southern Brazil is the Mixed Ombrophilous Forest (MOF), a subtype of the Atlantic Forest and one of the biodiversity hotspots on Earth. We sampled adult Odonata at 30 locations in the Floresta Nacional de São Francisco de Paula (FLONA-SFP), Rio Grande do Sul, Brazil, a national reserve which is divided into several sectors of MOF, planted Araucaria angustifolia, Pinus elliottii used for sustainable and financial purposes, and open fields. There are three types of aquatic environments in the reserve: lakes, swamps, and rivers/streams. Our aim was to obtain an overview of the species’ distribution patterns in the three types of aquatic environments and to evaluate the species occurring in lakes, an exclusively man-made habitat in this area. We recorded 46 species from seven odonate families; 25 species (x = 5.71 ± 1.77 SD) occurring in rivers/ streams, 24 in lakes (11.57 ± 2.15) and 21 in swamps (5.22 ± 3.60). Using Non-metric Multidimensional Scaling (NmDS), we showed that the species composition differed clearly between the three types of aquatic habitats. While swamps and rivers/streams had a relatively similar and uniform species composition, species in the lakes were more varied but the total species number was almost as high as that of the rivers/streams. The lake communities also differed distinctly from those of the other habitats, and we assume that the lake species originate from other degraded areas in the vicinity, indicating that the remains of the Atlantic Forest has already been strongly altered by humans. Given the poor knowledge of the Odonata in the Atlantic Forest/MOF, we hope that our study may increase the understanding of the communities, and contribute to the development of conservation measures for this fragmented biome.

  • 110.
    Renner, Samuel
    et al.
    Centro Universitário Univates, Lajeado, RS, Brazil.
    Périco, Eduardo
    Centro Universitário Univates, Lajeado, RS, Brazil.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Martins dos Santos, Daniel
    Centro Universitário Univates, Lajeado, RS, Brazil.
    Consatti, Guilherme
    Centro Universitário Univates, Lajeado, RS, Brazil.
    Dragonflies (Odonata) from the Taquari River valley region, Rio Grande do Sul, Brazil2015In: Check List, ISSN 1809-127X, E-ISSN 1809-127X, Vol. 11, no 5, article id 1740Article in journal (Refereed)
    Abstract [en]

    A survey of Odonata was carried out in the central region of the state of Rio Grande do Sul: the Taquari River valley. This region was originally covered by deciduous and Semi-deciduous Atlantic Forest, which today only exist in a highly fragmented environment mainly due to agricultural activities. Our survey was conducted in 12 municipalities from this region, between March 2011 and April 2013. Aiming a general overview of the species composition, our sampling sites included lakes, bogs, small streams and river sections, all inside or surrounded by small forest fragments or forest areas. Fifty species of Odonata were collected comprising 29 genera and seven families. The dominant families were Libellulidae (40%) and Coenagrionidae (36%), while Aeshindae, Gomphidae and Lestidae each only comprise 6% of the total number of species. The findings revealed the presence of a highly diverse odonate assemblage, mainly represented by generalist species in human disturbed fragments and a few forest specialist species in the best preserved remnants only.

  • 111.
    Renner, Samuel
    et al.
    Universidade do Vale do Taquari, Lajeado, Brazil.
    Périco, Eduardo
    Universidade do Vale do Taquari, Lajeado, Brazil.
    Schmidt Dalzochio, Marina
    Universidade do Vale do Taquari, Lajeado, Brazil.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Water body type and land cover shape the dragonfly communities (Odonata) in the Pampa biome, Rio Grande do Sul, Brazil2018In: Journal of Insect Conservation, ISSN 1366-638X, E-ISSN 1572-9753, Vol. 22, no 1, p. 113-125Article in journal (Refereed)
    Abstract [en]

    The biogeographical region known as the Pampa biome in southern Brazil, was originally mainly covered with open fields or grassland, with areas of riparian forest surrounding the water bodies. Today this landscape appears highly fragmented due to agricultural activities such as rice cultivation, extensive cattle farming, and forest plantations. Studies have shown that the Pampa biome has high levels of biodiversity and endemism, but with regard to invertebrates, this biome is still one of the least known in Brazil. We therefore designed a study comparing the dragonfly (Odonata) communities to environmental and landscape features in this area, measuring diversity by species richness, relative abundance and Shannon index. Our results showed that the Pampa is a biome very rich in odonates, and that the species communities are highly dependent on the environmental conditions of the area. Habitats such as Rivers/Streams, bordered by native grasslands and riparian forests, were shown to harbour communities that were ecologically more complex and sensitive than other habitat types. Man-made lakes and agricultural areas displayed lower levels of biodiversity and odonate communities dominated by generalist species. By combining data on the communities of Odonata and other taxa, our analyses may be instrumental in determining priority areas for future conservation measures within the area. © 2018, Springer International Publishing AG, part of Springer Nature.

  • 112.
    Renner, Samuel
    et al.
    Lab de Evolução e Ecologia, Centro Universitário Univates, Lajeado, RS, Brazil.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Périco, Eduardo
    Lab de Evolução e Ecologia, Centro Universitário Univates, Lajeado, RS, Brazil.
    Testing Dragonflies as Species Richness Indicators in a Fragmented Subtropical Atlantic Forest Environment2015In: Neotropical Entomology, ISSN 1519-566X, E-ISSN 1678-8052, Vol. 45, no 3, p. 231-239Article in journal (Refereed)
    Abstract [en]

    We surveyed 15 bodies of water among remnants of the Atlantic Forest biome in southern Brazil for adult dragonflies and damselflies to test whether an empirical selection method for diversity indicators could be applied in a subtropical ecosystem, where limited ecological knowledge on species level is available. We found a regional species pool of 34 species distributed in a nested subset pattern with a mean of 11.2 species per locality. There was a pronounced difference in species composition between spring, summer, and autumn, but no differences in species numbers between seasons. Two species, Homeoura chelifera (Selys) and Ischnura capreolus (Hagen), were the strongest candidates for regional diversity indicators, being found only at species-rich localities in our surveyed area and likewise in an undisturbed national forest reserve, serving as a reference site for the Atlantic Forest. Using our selection method, we found it possible to obtain a tentative list of diversity indicators without having detailed ecological information of each species, providing a reference site is available for comparison. The method thus allows for indicator species to be selected in blanco from taxonomic groups that are little known. We hence argue that Odonata can already be incorporated in ongoing assessment programs in the Neotropics, which would also increase the ecological knowledge of the group and allow extrapolation to other taxa. © 2015, Sociedade Entomológica do Brasil.

  • 113.
    Rosenberg, Mikaela
    et al.
    Halmstad University, School of Education, Humanities and Social Science.
    Lidström, Sara
    Halmstad University, School of Education, Humanities and Social Science.
    Utomhuspedagogikens rumsliga ramar2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Utomhuspedagogik har speglats som en positiv metod lärare kan använda sig av i sin undervisning. Litteraturstudien belyser hur forskningen ser på utomhuspedagogik samt hur forskare lyfter och kritiserar metoden. De delade aspekter som lyfts fram sker ur ett lärarperspektiv där lärare bland annat anser att utomhuspedagogiken tar mycket resurser och tid från skolans värld, samtidigt som de talar för de gynnande effekterna på elevers kunskapsutveckling.Syftet med denna studie är att undersöka utomhuspedagogikens påverkan på elevers kunskapsutveckling inom ämnet biologi utifrån undervisningsplatsen. Utifrån tidigare forskning har en litteraturstudie gjorts där vårt empiriska material består av vetenskapliga artiklar.Genom vår studie fick vi fram att användningen av utomhuspedagogik i ämnet biologi erhöll både positiva och negativa aspekter men att det saknas forskning kring kritiska infallsvinklar om metoden. Ytterligare forskning behövs inom användningen av metoden i ämnet för att ge eleverna möjligheter till ett gynnsamt lärande.

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    fulltext
  • 114.
    Rögnvaldsson, Thorsteinn
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    Etchells, Terence A
    School of Computing and Mathematical Sciences, Liverpool John Moores University.
    You, Liwen
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    Garwicz, Daniel
    Department of Molecular Medicine and Surgery, Karolinska Institutet.
    Jarman, Ian
    School of Computing and Mathematical Sciences, Liverpool John Moores University.
    Lisboa, Paulo J G
    School of Computing and Mathematical Sciences, Liverpool John Moores University.
    How to find simple and accurate rules for viral protease cleavage specificities2009In: BMC Bioinformatics, ISSN 1471-2105, E-ISSN 1471-2105, Vol. 10, p. 149-156Article in journal (Refereed)
    Abstract [en]

    BACKGROUND:

    Proteases of human pathogens are becoming increasingly important drug targets, hence it is necessary to understand their substrate specificity and to interpret this knowledge in practically useful ways. New methods are being developed that produce large amounts of cleavage information for individual proteases and some have been applied to extract cleavage rules from data. However, the hitherto proposed methods for extracting rules have been neither easy to understand nor very accurate. To be practically useful, cleavage rules should be accurate, compact, and expressed in an easily understandable way.

    RESULTS:

    A new method is presented for producing cleavage rules for viral proteases with seemingly complex cleavage profiles. The method is based on orthogonal search-based rule extraction (OSRE) combined with spectral clustering. It is demonstrated on substrate data sets for human immunodeficiency virus type 1 (HIV-1) protease and hepatitis C (HCV) NS3/4A protease, showing excellent prediction performance for both HIV-1 cleavage and HCV NS3/4A cleavage, agreeing with observed HCV genotype differences. New cleavage rules (consensus sequences) are suggested for HIV-1 and HCV NS3/4A cleavages. The practical usability of the method is also demonstrated by using it to predict the location of an internal cleavage site in the HCV NS3 protease and to correct the location of a previously reported internal cleavage site in the HCV NS3 protease. The method is fast to converge and yields accurate rules, on par with previous results for HIV-1 protease and better than previous state-of-the-art for HCV NS3/4A protease. Moreover, the rules are fewer and simpler than previously obtained with rule extraction methods.

    CONCLUSION:

    A rule extraction methodology by searching for multivariate low-order predicates yields results that significantly outperform existing rule bases on out-of-sample data, but are more transparent to expert users. The approach yields rules that are easy to use and useful for interpreting experimental data.

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    FULLTEXT01
  • 115.
    Rögnvaldsson, Thorsteinn
    et al.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), Halmstad Embedded and Intelligent Systems Research (EIS).
    Häkkinen, Jari
    Department of Theoretical Physics, Lund University, Sölvegatan 14A, SE-223 62 Lund, Sweden.
    Lindberg, Claes
    Molecular Sciences, AstraZeneca RandD Lund, SE-221 87 Lund, Sweden.
    Marko-Varga, György
    Molecular Sciences, AstraZeneca RandD Lund, SE-221 87 Lund, Sweden.
    Potthast, Frank
    Funct. Genomics Center Zürich, Winterthurerstr. 190 Y32 H52, CH-8057 Zürich, Switzerland.
    Samuelsson, Jim
    Genedata GmbH, Lena-Christ-Str. 50, D-82152 Martinsried, Germany.
    Improving automatic peptide mass fingerprint protein identification by combining many peak sets2004In: Journal of chromatography. B, ISSN 1570-0232, E-ISSN 1873-376X, Vol. 807, no 2, p. 209-215Article in journal (Refereed)
    Abstract [en]

    An automated peak picking strategy is presented where several peak sets with different signal-to-noise levels are combined to form a more reliable statement on the protein identity. The strategy is compared against both manual peak picking and industry standard automated peak picking on a set of mass spectra obtained after tryptic in gel digestion of 2D-gel samples from human fetal fibroblasts. The set of spectra contain samples ranging from strong to weak spectra, and the proposed multiple-scale method is shown to be much better on weak spectra than the industry standard method and a human operator, and equal in performance to these on strong and medium strong spectra. It is also demonstrated that peak sets selected by a human operator display a considerable variability and that it is impossible to speak of a single “true” peak set for a given spectrum. The described multiple-scale strategy both avoids time-consuming parameter tuning and exceeds the human operator in protein identification efficiency. The strategy therefore promises reliable automated user-independent protein identification using peptide mass fingerprints.

  • 116.
    Rögnvaldsson, Thorsteinn
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Häkkinen, Jari
    Department of Theoretical Physics, Lund University, Lund, Sweden.
    Samuelsson, Jim
    BioBridge Computing, Lund, Sweden.
    Lindberg, Claes
    AstraZeneca R and D, Lund, Sweden.
    Marko-Varga, György
    AstraZeneca R and D, Lund, Sweden.
    Potthast, Frank
    AstraZeneca R and D, Mölndal, Sweden.
    Improved protein identification in mammalian cells using a new automatic peak detection algorithm2002In: Proceedings - 50th ASMS Conference on Mass Spectrometry and Allied Topics: June 2-6, 2002, Orlando, Florida, Santa Fe: ASMS , 2002, p. 785-786Conference paper (Refereed)
    Abstract [en]

    A comparison of two automatic peak detection algorithms is presented. One algorithm comes with the Voyager 5 Data ExplorerTM program, the other is a new algorithm called Pepex® (short for PEptide Peak Extractor) from BioBridge Computing. The peak sets selected with both tools have been compared, against each other and against manual peak selections, on a large set of mass spectra obtained after tryptic in gel digestion of 2D-gel samples from human fetal fibroblasts. It is shown how much variation there is in peak sets, both when selected by human operators and when selected by automatic peak detection algorithms. This variation has been used as an advantage to gain significantly better protein identification results, using the Pepex tool, than what an experienced mass spectroscopist has achieved on the same data. The strongest improvement has been observed in weak spectra, where the signal peak intensities are low.

  • 117.
    Rögnvaldsson, Thorsteinn
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Intelligent systems (IS-lab).
    You, Liwen
    Lund University, Department of Theoretical Physics, Lund, Sweden.
    Why neural networks should not be used for HIV-1 protease cleavage site prediction2004In: Bioinformatics, ISSN 1367-4803, E-ISSN 1367-4811, Vol. 20, no 11, p. 1702-1709Article in journal (Refereed)
    Abstract [en]

    Several papers have been published where non-linear machine learning algorithms, e.g. artificial neural networks, support vector machines and decision trees, have been used to model the specificity of the HIV-1 protease and extract specificity rules. We show that the dataset used in these studies is linearly separable and that it is a misuse of nonlinear classifiers to apply them to this problem. The best solution on this dataset is achieved using a linear classifier like the simple perceptron or the linear support vector machine, and it is straightforward to extract rules from these linear models. We identify key residues in peptides that are efficiently cleaved by the HIV-1 protease and list the most prominent rules, relating them to experimental results for the HIV-1 protease. Motivation: Understanding HIV-1 protease specificity is important when designing HIV inhibitors and several different machine learning algorithms have been applied to the problem. However, little progress has been made in understanding the specificity because nonlinear and overly complex models have been used. Results: We show that the problem is much easier than what has previously been reported and that linear classifiers like the simple perceptron or linear support vector machines are at least as good predictors as nonlinear algorithms. We also show how sets of specificity rules can be generated from the resulting linear classifiers.

  • 118.
    Sahlén, Göran
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Bernard, Rafal
    Department of General Zoology, Adam Mickiewicz University, Poznan, Poland.
    Rivera, Adolfo Cordero
    Departamento de Ecoloxía e Bioloxía Animal, Universidade de Vigo, EUET Forestal, Campus Universitario, Pontevedra, Spain.
    Ketelaar, Robert
    Dutch Butterfly Conservation / Dutch Society for the Preservation of Nature, Eindhoven, The Netherlands.
    Suhling, Frank
    Institute of Geoecology, Dpt of Environmental System Analysis, Technical University of Braunschweig, Braunschweig, Germany.
    Critical species of Odonata in Europe2004In: International Journal of Odonatology, ISSN 1388-7890, Vol. 7, no 2, p. 385-398Article in journal (Refereed)
    Abstract [en]

    The status of the odonate fauna of Europe is fairly well known, but the current IUCN Red List presents only six species out of ca 130, two of which are actually out of danger today. In this paper we propose a tentative list of 22 possibly declining or threatened species in the region. For the majority, reliable data of population size and possible decline is still lacking. Also 17 endemic species are listed, most occurring in the two centres of endemism in the area: the south-eastern (mountains and islands) and the western Mediterranean. These species should receive extra attention in future updates of the world Red List due to their limited distribution. The extreme variation in biomes and the human exploitation of habitats make conservation planning complicated in Europe. Within the EU, the FFH directive is a working tool aiding conservation. However, the species included do not fully correspond to those on the current Red List, nor to those discussed in this paper. We believe that future conservation efforts should focus on the most valuable and threatened habitats in each sub-region. Active conservation measures could be implemented on a European scale, provided that research will establish a solid ground for such measures. © 2004 Taylor & Francis Group, LLC.

  • 119.
    Sahlén, Göran
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    Haase, Susann
    Tech Univ Carolo Wilhelmina Braunschweig, Inst Geookol, D-38106 Braunschweig, Germany.
    Suhling, Frank
    Tech Univ Carolo Wilhelmina Braunschweig, Inst Geookol, D-38106 Braunschweig, Germany.
    Morphology of dragonfly larvae along a habitat gradient: interactions with feeding behaviour and growth (Odonata: Libellulidae)2008In: International Journal of Odonatology, ISSN 1388-7890, Vol. 11, no 2, p. 225-240Article in journal (Refereed)
    Abstract [en]

    It has been shown that life history, behavioural as well as morphological traits vary with the habitats occupied by odonate larvae. Here we ask the following questions: (1) Are the morphological traits, which are associated with perception and foraging, related to the larval habitat? (2) Do these traits influence foraging success and growth rate? We analysed the morphology of species pairs belonging to the genera Crocothemis, Orthetrum and Trithemis; one species in each pair occurring in perennial spring-fed streams, the other able to develop in temporary waters. A PCA reveals four principal components of morphological characters which may be expressed as PC1: prey handling, PC2: visual perception, and PC3 and PC4: density of long and short setae on the feet. The variances of PC1, PC2 and PC3 were affected by phylogeny. PC1, PC2 and PC4 differed between habitats. Species of perennial springs had larger values for visual perception. These waters are clear and larger eyes should be beneficial. But, a high PC2 value was associated with low growth rate and did not affect foraging success. We therefore conclude that investment in better sight made by perennial water species may reflect the need of avoiding predators. Development in temporary waters mainly requires rapid growth and species may not be capable to invest also in visual perception. PC1 was negatively correlated with foraging behaviour and PC3 was positively so. This indicates the importance of prey capture mode to foraging success, which may, however, not translate into a higher growth rate.

  • 120.
    Sahlén, Göran
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Hedström, Ingemar
    Boston University, College of Arts and Sciences, Boston, MA, USA.
    The larva of Mecistogaster linearis, with notes on its abundance in lowland rainforest of Costa Rica (Odonata: Pseudostigmatidae)2005In: International Journal of Odonatology, ISSN 1388-7890, Vol. 8, no 1, p. 59-66Article in journal (Refereed)
    Abstract [en]

    The larva of Mecistogaster linearis is described and illustrated from specimens collected within or near the Río Dantas Wildlife Refuge at the north-western border of the Barbilla National Park on the Costa Rican Caribbean slope. Characters of F-0 larvae permit easy separation from Megaloprepus caerulatus, a species coexisting with M. linearis. Diagnostic characters include overall colour, shape of head, prementum and caudal gills. Exuviae may be determined using shape of mandibles. Two types of branched setae are present on tibiae and tarsi. Most are 3-branched but on front tarsi they are instead feather-shaped. It is suggested that these setae are used for eye-cleaning. M. linearis was a relatively rare but regularly occurring species in the study area throughout the 3-year study period. © 2005 Taylor & Francis Group, LLC.

  • 121.
    Sahlén, Göran
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    Kalkman, Vincent J.
    Boudot, Jean-Pierre
    Bernard, Rafał
    Conze, Klaus-Jürgen
    De Knijf, Geert
    Dyatlova, Elena
    Ferreira, Sónia
    Jovic, Miloš
    Ott, Jürgen
    Riservato, Elisa
    European Red List of Dragonflies2010Report (Other academic)
    Abstract [en]

    The European Red List is a review of the conservation status of c.6,000 European species (mammals, reptiles, amphibians, freshwater fishes, butterflies, dragonflies, and selected groups of beetles, molluscs, and vascular plants) according to IUCN regional Red Listing guidelines. It identifies those species that are threatened with extinction at the regional level – in order that appropriate conservation action can be taken to improve their status. This Red List publication summarises results for European Dragonflies.

  • 122.
    Sahlén, Göran
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Suhling, Frank
    Institut für Geoökologie, Technische UniversitätBraunschweig, Braunschweig, Germany.
    Martens, Andreas
    Institut für Biologie und Schulgartenentwicklung, Pädagogische Hochschule Karlsruhe,Karlsruhe, Germany.
    Gorb, Stanislav N.
    Zoological Institute: Functional Morphology and Biomechanics, Kiel University, Kiel, Germany.
    Fincke, Ola M.
    Ecologyand Evolutionary Biology Program, Department of Biology, University of Oklahoma, Norman, OK, U.S.A..
    For consistency’s sake? A reply to Bybee et al.2016In: Systematic Entomology, ISSN 0307-6970, E-ISSN 1365-3113, Vol. 41, no 2, p. 307-308Article in journal (Refereed)
  • 123.
    Sandberg, Mikael
    et al.
    Halmstad University, School of Education, Humanities and Social Science, Center for Social Analysis (CESAM).
    Lundberg, Per
    Lunds universitet, Lund, Sweden.
    Political Institutions and Their Historical Dynamics2012In: PLoS ONE, E-ISSN 1932-6203, Vol. 7, no 10, article id e45838Article in journal (Refereed)
    Abstract [en]

    Traditionally, political scientists define political institutions deductively. This approach may prevent from discovery of existing institutions beyond the definitions. Here, a principal component analysis was used for an inductive extraction of dimensions in Polity IV data on the political institutions of all nations in the world the last two centuries. Three dimensions of institutions were revealed: core institutions of democracy, oligarchy, and despotism. We show that, historically and on a world scale, the dominance of the core institutions of despotism has first been replaced by a dominance of the core institutions of oligarchy, which in turn is now being followed by an increasing dominance by the core institutions of democracy. Nations do not take steps from despotic, to oligarchic and then to democratic institutions, however. Rather, nations hosting the core democracy institutions have succeeded in historically avoiding both the core institutions of despotism and those of oligarchy. On the other hand, some nations have not been influenced by any of these dimensions, while new institutional combinations are increasingly influencing others. We show that the extracted institutional dimensions do not correspond to the Polity scores for autocracy, “anocracy” and democracy, suggesting that changes in regime types occur at one level, while institutional dynamics work on another. Political regime types in that sense seem “canalized”, i.e., underlying institutional architectures can and do vary, but to a considerable extent independently of regime types and their transitions. The inductive approach adds to the deductive regime type studies in that it produces results in line with modern studies of cultural evolution and memetic institutionalism in which institutions are the units of observation, not the nations that acts as host for them.

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  • 124.
    Schjoerring, Jan K.
    et al.
    Plant Nutrition Laboratory, Roy. Vet. and Agric. University, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.
    Husted, Søren
    Plant Nutrition Laboratory, Roy. Vet. and Agric. University, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.
    Mäck, Gisela
    Plant Nutrition Laboratory, Roy. Vet. and Agric. University, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.
    Mattsson, Marie
    Plant Nutrition Laboratory, Roy. Vet. and Agric. University, Denmark.
    The regulation of ammonium translocation in plants2002In: Journal of Experimental Botany, ISSN 0022-0957, E-ISSN 1460-2431, Vol. 53, no 370, p. 883-890Article in journal (Refereed)
    Abstract [en]

    Much controversy exists about whether or not NH+4 is translocated in the xylem from roots to shoots. In this paper it is shown that such translocation can indeed take place, but that interference from other metabolites such as amino acids and amines may give rise to large uncertainties about the magnitude of xylem NH+4 concentrations. Elimination of interference requires sample stabilization by, for instance, formic acid or methanol. Subsequent quantification of NH+4 should be done by the OPA-fluorometric method at neutral pH with 2-mercaptoethanol as the reducing agent since this method is sensitive and reliable. Colorimetric methods based on the Berthelot reaction should never be used, as they are prone to give erroneous results. Significant concentrations of NH+4, exceeding 1 mM, were measured in both xylem sap and leaf apoplastic solution of oilseed rape and tomato plants growing with NO-3 as the sole N source. When NO-3 was replaced by NH+4, xylem sap NH+4 concentrations increased with increasing external concentrations and with time of exposure to NH+4. Up to 11% of the translocated N was constituted by NH+4. Glutamine synthetase (GS) incorporates NH+4 into glutamine, but root GS activity and expression were repressed when high levels of NH+4 were supplied. Ammonium concentrations measured in xylem sap sampled just above the stem base were highly correlated with NH+4 concentrations in apoplastic solution from the leaves. Young leaves tended to have higher apoplastic NH+4 concentrations than older non-senescing leaves. The flux of NH+4 (concentration multiplied by transpirational water flow) increased with temperature despite a decline in xylem NH+4 concentration. Retrieval of leaf apoplastic NH+4 involves both high and low affinity transporters in the plasma membrane of mesophyll cells. Current knowledge about these transporters and their regulation is discussed.

  • 125.
    Schmidt Dalzochio, Marina
    et al.
    Ecology and Evolution, University of Vale do Taquari, UNIVATES, Lajeado, Brazil.
    Périco, Eduardo
    Ecology and Evolution, University of Vale do Taquari, UNIVATES, Lajeado, Brazil.
    Renner, Samuel
    Ecology and Evolution, University of Vale do Taquari, UNIVATES, Lajeado, Brazil.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Effect of tree plantations on the functional composition of Odonata species in the highlands of southern Brazil2018In: Hydrobiologia, ISSN 0018-8158, E-ISSN 1573-5117, Vol. 808, no 1, p. 283-300Article in journal (Refereed)
    Abstract [en]

    Changes in biodiversity have mainly been assessed using taxonomical diversity indices. Although these approaches contribute to the scientific understanding of species richness and composition patterns, trait-based metrics may be more useful for detecting responses to land use change. We used odonates as a model system to compare traits composition in mixed ombrophilous forest (MOF) and tree plantations: exotic species (Pinus sp.) and native species (Araucaria angustifolia). Our goal was to understand and compare how each vegetation type affects the selection of species traits, and which factors are responsible for the presence of the species in the environment. We recorded 36 Odonata species distributed across 14 functional groups. The functional composition varied between MOF and exotic tree plantations and was similar between these two habitats and native tree plantations. Native forest favoured specialist traits. Our results suggest that the conversion of MOF to tree plantations, especially exotic ones, results in a shift to less specialized Odonata communities with altered functional group composition. This result highlights the negative impact associated with the conversion of native forests into exotic plantations. Our results show that odonates with specialist traits are limited to natural forest sites, which makes the conservation of such areas crucial. © 2017 Springer International Publishing AG, part of Springer Nature

  • 126.
    Selck, Henriette
    et al.
    Roskilde University, Roskilde, Denmark.
    Adamsen, Peter B.
    Ramboll Environ, Copenhagen, Denmark.
    Backhaus, Thomas
    University of Gothenburg, Gothenburg, Sweden.
    Banta, Gary T.
    Roskilde University, Roskilde, Denmark.
    Bruce, Peter K.H.
    Stockholm University, Stockholm, Sweden.
    Burton Jr., G. Allen
    University of Michigan, Ann Arbor, Michigan, USA.
    Butts, Michael B.
    DHI Group, Copenhagen, Denmark.
    Boegh, Eva
    Roskilde University, Roskilde, Denmark.
    Clague, John J.
    Simon Fraser University, Burnaby, British Columbia, Canada.
    Dinh, Khuong V.
    Technical University of Denmark, Kongens Lyngby, Denmark.
    Doorn, Neelke
    Delft University of Technology, Delft, The Netherlands.
    Gunnarsson, Jonas S.
    Stockholm University, Stockholm, Sweden.
    Hauggaard-Nielsen, Henrik
    Roskilde University, Roskilde, Denmark.
    Hazlerigg, Charles
    Enviresearch, Newcastle-upon-Tyne, United Kingdom of Great Britain and Northern Ireland.
    Hunka, Agnieszka D.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Jensen, John
    Aarhus University, Silkeborg, Denmark.
    Lin, Yan
    Norwegian Institute for Water Research, Oslo, Norway.
    Loureiro, Susana
    Department of Biology & CESAM, University of Aveiro, Aveiro, Portugal.
    Miraglia, Simona
    Technical University of Denmark, Kongens Lyngby, Denmark.
    Munns Jr., Wayne R.
    US Environmental Protection Agency, Narragansett, Rhode Island, USA.
    Nadim, Farrokh
    Norwegian Geotechnical Institute, Oslo, Norway.
    Palmqvist, Annemette
    Roskilde University, Roskilde, Denmark.
    Rämö, Robert A.
    Stockholm University, Stockholm, Sweden.
    Seaby, Lauren P.
    Roskilde University, Roskilde, Denmark.
    Syberg, Kristian
    Roskilde University, Roskilde, Denmark.
    Tangaa, Stine R.
    Roskilde University, Roskilde, Denmark.
    Thit, Amalie
    Roskilde University, Roskilde, Denmark.
    Windfeld, Ronja
    Roskilde University, Roskilde, Denmark.
    Zalewski, Maciej
    European Regional Centre for Ecohydrology (Polish Academy of Sciences), Lodz, Poland.
    Chapman, Peter M.
    Chapema Environmental Strategies, North Vancouver, British Columbia, Canada.
    Assessing and managing multiple risks in a changing world – The Roskilde recommendations2017In: Environmental Toxicology and Chemistry, ISSN 0730-7268, E-ISSN 1552-8618, Vol. 36, no 1, p. 7-16Article in journal (Refereed)
    Abstract [en]

    Roskilde University (Denmark) hosted a November 2015 workshop, Environmental Risk—Assessing and Managing Multiple Risks in a Changing World. This Focus article presents the consensus recommendations of 30 attendees from 9 countries regarding implementation of a common currency (ecosystem services) for holistic environmental risk assessment and management; improvements to risk assessment and management in a complex, human-modified, and changing world; appropriate development of protection goals in a 2-stage process; dealing with societal issues; risk-management information needs; conducting risk assessment of risk management; and development of adaptive and flexible regulatory systems. The authors encourage both cross-disciplinary and interdisciplinary approaches to address their 10 recommendations: 1) adopt ecosystem services as a common currency for risk assessment and management; 2) consider cumulative stressors (chemical and nonchemical) and determine which dominate to best manage and restore ecosystem services; 3) fully integrate risk managers and communities of interest into the risk-assessment process; 4) fully integrate risk assessors and communities of interest into the risk-management process; 5) consider socioeconomics and increased transparency in both risk assessment and risk management; 6) recognize the ethical rights of humans and ecosystems to an adequate level of protection; 7) determine relevant reference conditions and the proper ecological context for assessments in human-modified systems; 8) assess risks and benefits to humans and the ecosystem and consider unintended consequences of management actions; 9) avoid excessive conservatism or possible underprotection resulting from sole reliance on binary, numerical benchmarks; and 10) develop adaptive risk-management and regulatory goals based on ranges of uncertainty. © 2016 SETAC

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  • 127.
    Sjövall, Anna
    Halmstad University, School of Business, Engineering and Science.
    Inventering av kärlväxter i Vapnö grustäkt2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Nitrogen deposition and changes in agriculture and forestry have led to a decrease of sandy habitats in Sweden due to regrowth of vegetation. Sand- and gravelpits can act as refuges for vascular plants that require the dry and nutrient-poor conditions of sandy soils. Vapnö gravelpit in Halland county in Sweden was surveyed in 2010 and proved to hold a high biodiversity including 145 species of vascular plants, of which four were red-listed. Now, seven years later, the purpose of this study was to see how the composition of vascular plants has changed since then. The area was studied on ten occasions from April to August, and all species of vascular plants were noted. The study resulted in a list of 224 species, of which 63 were remaining since 2010 and 161 were new species for the area. There were five red-listed species: Dianthus armeria (EN), Genista pilosa (NT), Thymus serpyllum (NT), Ulmus glabra (CR) and Acer campestre (CR). The total number of species and red-listed species have increased, suggesting a positive development of the biodiversity of the area. The high species diversity is probably due to the open, varied landscape and the presence of the red-listed species due to the increasingly rare sandy habitat. The diversity of vascular plants in the area is threatened by regrowth of vegetation, as well as the invasive species Lupinus polyphyllus and Fallopia japonica. These threats can be counteracted by disturbance in the form of mowing or digging up plants, prescribed burning or grazing.

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  • 128.
    Skoglund, Linda
    Halmstad University, School of Business and Engineering (SET).
    Artsamhällen av trollsländor (Odonata) i norrländska tjärnar: identifiering av möjliga indikatorarter för artmångfald2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A field study of dragonfly larvae was performed in 20 lakes situated in boreal forest in northern Sweden (in the southeast of Norrbotten county), accompanied by the study of several habitat variables within the locales; fish presence, composition of water vegetation, forestry and the distribution of Sphagnum moss. None of these variables had a proven effect on the species composition of Odonata. This may be due to the fact that species occurring in the north part of the country are generally more tolerant to environmental variables compared to species with a more southern focus of distribution. A shorter growth season implies prolonged life cycles and should in all probability bring about a greater need for habitat tolerance. When a species occurrence is not strictly random the species richness within a region increases/decreases as a result of the presence/absence of specific species which are sensitive to particular variables in their surroundings (deconstructive approach to species richness). Indicator species (indicating general species richness) were distinguished by implementing an analysis of nestedness and the result was compared to a similar study conducted for central Sweden (Sahlén and Ekestubbe, 2001). E. najas and L. quadrimaculata came forth as suitable indicator species for northern boreal freshwater habitats in this study. In the north they displayed specialist tendencies and were highly selective in their choice of habitats. The same species appears in a very different ecological context when localized to southern Sweden where they are considered trivial species. In addition, temporal follow-ups (repeated stocktakings) of the species composition of small freshwater habitats in this region, and the establishment of accompanying nestedness matrices will allow for the detection of ecological shifts within particular species. These would indicate ongoing restructuring of the Odonate communities and yield information about the impact of climate change.        

  • 129.
    Skrijelj, Lejla
    Halmstad University, School of Business, Engineering and Science.
    Population dynamics and management strategies of stray and free-ranging dogs in Bor, Serbia2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Dogs are one of the most widespread carnivore and the third most invasive mammal, after cats and rodents. Stray dogs affect wildlife negatively by predation, disturbance, disease spreading, competition and hybridization with other wild canids. Even in urban environments stray dogs cause problems such as disturbance, pollution, traffic accidents, bites and risk of disease spreading. Serbia is one of many countries in the Balkan region that has a problem with overpopulation of stray dogs. The aim of this study is to investigate the population dynamics of stray dogs in Bor, Serbia and discuss different dog population management strategies. A total of 361 stray dogs were registered, 111 male dogs, 85 female dogs and 165 dogs with undetermined sex. 55 dogs (15.23%) were estimated to be older than 7 years old, 262 dogs (72.57%) were estimated to be between 3-7 years old, 30 dogs (8.31%) were estimated to be between 6-24 months old and 14 dogs (3.87) were estimated to be between 0-6 months old. No dogs showed any signs of rabies or CDV (canine distemper virus) and 241 stray dogs (66.75%) seemed healthy. 120 stray dogs (33.25%) did however have some kind of impaired health. To achieve a stop in the population increase,70% sterilisation rate is required and to teach responsible dog ownership. The stray dogs showed different reactions towards people, 164 dogs (45.42%) were neutral and 100 dogs (27.70%) showed no fear or aggression towards humans and gladly interacted. Since the dogs are highly accessible, they would be acceptable for a TNR (trap-neuter-release) program and male dogs need to be prioritised considering their dispersal patterns.

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  • 130.
    Spångfors, Helena
    Halmstad University, School of Business, Engineering and Science.
    Malformation in different species of benthic diatoms in three herbicide polluted streams in southern Sweden2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Målet med den här studien var att undersöka kiselalger och dess eventuella missbildningar i tre vattendrag i södra Sverige - Höje å, Skivarpsån och M42. Kiselalger används som bioindikator för vattenkvalitet i hela Europa, men de befintliga kiselalgsindexen visar inte eventuell förekomst av miljöfarliga ämnen. Det har dock visats att en förekomst > 1 % av missbildade kiselalger indikerar påverkan av miljöfarliga ämnen, såsom pesticider och tungmetaller. Denna studie är en av få som har undersökt kiselalgers missbildningar i vattendrag som är mer eller mindre påverkade av herbicider. Sex prov från varje vattendrag analyserades - kiselalger räknades och identifierades till artnivå och missbildningar dokumenterades och kategoriserades. Vattendragen delades in efter PTI (Pesticide Toxicity Index), där Höje å hade lägst PTI och ansågs minst påverkad av herbicider. Skivarpsån och M42 hade högre PTI, och ansågs därför ha en högre herbicidpåverkan.

    Det fanns en signifikant skillnad i missbildningsfrekvens vattendragen emellan, den kunde dock inte kopplas till PTI. Både Höje å och M42 hade > 1 % missbildningar. Skivarpsåns missbildningsfrekvens var < 1 % trots vattendragets relativt höga PTI. Det är möjligt att missbildningsfrekvensen bättre hade reflekterat PTI om herbicidprovtagningen skett någon månad tidigare, då herbicidhalter kan variera och kiselalger har visat sig kunna spegla ett vattendrags mående upp till tre månader bakåt i tiden. En annan förklaring till en varierande missbildningsfrekvens kan vara en lika varierande artsammansättning. Vissa arter är mindre “benägna” att missbildas än andra - ett prov som domineras av sådana skulle därför kunna innehålla få missbildningar trots eventuell miljögiftspåverkan. Det krävs dock ytterligare studier för att bättre förstå kiselalgers missbildningar i förhållande till herbicider.

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  • 131.
    Strand, John A.
    et al.
    Hushållningssällskapet Halland.
    Weisner, Stefan
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Kävlingeåprojektet – utvärdering av etapp I-III: Rapport på uppdrag av Programberedningen för Kävlingeåprojektet2010Report (Other academic)
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  • 132.
    Strand, John A.
    et al.
    Limnology, Lund University, Lund, Sweden.
    Weisner, Stefan
    Limnology, Lund University, Lund, Sweden.
    Wave exposure related growth of epiphyton: Implications for the distribution of submerged macrophytes in eutrophic lakes1996In: Hydrobiologia, ISSN 0018-8158, E-ISSN 1573-5117, Vol. 325, no 2, p. 113-119Article in journal (Refereed)
    Abstract [en]

    The distribution of submerged macrophytes in eutrophic lakes has been found to be skewed towards sites with intermediate exposure to waves. Low submerged macrophyte biomass at exposed sites has been explained by, for instance, physical damage from waves. The aim of this study was to investigate if lower biomass at sheltered sites compared to sites with intermediate exposure to waves can be caused by competition from epiphyton. Investigations were performed in eutrophic lakes in southern Sweden. Samples of submerged macrophytes and epiphytic algae on the macrophytes were taken along a wave exposure gradient. The amount of epiphyton (AFDW) per macrophyte biomass decreased with increased exposure. Biomass of submerged macrophytes, on the other hand, increased with increased exposure until a relatively abrupt disappearance of submerged vegetation occurred at high exposures. Production of epiphytic algae was monitored on artificial substrates from June to September at a sheltered and an exposed site in three lakes. It was higher at sheltered sites compared with exposed sites. We suggest that epiphytic algae may be an important factor in limiting the distribution of submerged macrophytes at sheltered sites in eutrophic lakes.

  • 133.
    Strand, John A.
    et al.
    Limnology, Department of Ecology, Lund University, Lund, Sweden.
    Weisner, Stefan E.B.
    Limnology, Department of Ecology, Lund University, Lund, Sweden .
    Dynamics of submerged macrophyte populations in response to biomanipulation2001In: Freshwater Biology, ISSN 0046-5070, E-ISSN 1365-2427, Vol. 46, no 10, p. 1397-1408Article in journal (Refereed)
    Abstract [en]

    1. A 6-year study (1992-97) of changes in submerged vegetation after biomanipulation was carried out in the eutrophicated Lake Finjasjon, Southern Sweden. Ten sites around the lake were revisited each year. At each site five samples of above-ground biomass were taken at 10 cm water depth intervals. An investigation of the seed bank at the 10 sites, and a grazing experiment where birds and large fish were excluded was also conducted. 2. Between 1992 and 1996, in shallow areas (water depth < 3 m), vegetation cover 2 increased from < 3 to 75% and above-ground biomass from < 1 to 100 g DW m(-2). Mean outer water depth increased from 0.3 to 2.5 m. Elodea canadensis and Myriophyllum spicatum accounted for > 95% of the increase in biomass and plant cover. The following year (1997), however, cover and above-ground biomass decreased, mainly attributable to the total disappearance of E. canadensis. Secchi depth increased after biomanipulation until 1996, but decreased again in 1997. 3. Total and mean number of submerged species increased after biomanipulation, probably as a result of the improved light climate. However, after the initial increase in species number there was a decrease during the following years, possibly attributed to competition from the rapidly expanding E. canadensis and M. spicatum. The lack of increase in species number after the disappearance of E. canadensis in 1997 implies that other factors also affected species richness. 4. A viable seed bank was not necessary for a rapid recolonization of submerged macrophytes, nor did grazing by waterfowl or fish delay the re-colonization of submerged macrophytes. 5. Submerged macrophytes are capable of rapid recolonization if conditions improve, even in large lakes such as Finjasjon (11 km(2)). Species that spread by fragments will increase rapidly and probably outcompete other species. 6. The results indicate that after the initial Secchi depth increase, probably caused by high zooplankton densities, submerged vegetation further improved the light climate. The decrease in macrophyte biomass in 1997 may have caused the observed increase in phosphorus and chlorophyll a, and the decrease in Secchi depth. We suggest that nutrient competition from periphyton, attached to the macrophytes, may be an important factor in limiting phytoplankton production, although other factors (e.g. zooplankton grazing) are also of importance, especially as triggers for the shift to a clear-water state.

  • 134.
    Strand, John A.
    et al.
    Limnology, Department of Ecology, Lund University, Lund, Sweden.
    Weisner, Stefan E.B.
    Limnology, Department of Ecology, Lund University, Lund, Sweden.
    Morphological plastic responses to water depth and wave exposure in an aquatic plant (Myriophyllum spicatum)2001In: Journal of Ecology, ISSN 0022-0477, E-ISSN 1365-2745, Vol. 89, no 2, p. 166-175Article in journal (Refereed)
    Abstract [en]

    1 We investigated morphological responses of the submerged macrophyte Myriophyllum spicatum L. to water depth and wave exposure when grown in the same substrate at two sites in two eutrophic lakes. Periphyton production was 4-8 times higher at sheltered than at wave-exposed sites and its influence was further investigated in a glasshouse experiment. Morphological responses in both experiments were compared by allometric analyses, with shoot weight as covariate. 2 In the field study, plants shoots exhibited similar responses (increased plant height and branch length, and decreased branch number) to sheltered conditions as to deep water. The partitioning between above- and below-ground biomass however, differed, with below-ground decreasing with an increasing water depth, but increasing or remaining unaffected at sheltered compared with exposed conditions. 3 In the glasshouse experiment, plant responses to water depth were similar to those in the field study. Furthermore, plant height increased when plants were overgrown with periphyton. 4 High production of periphytic algae at sheltered sites appears to cause light limitation of macrophytes. However, other factors such as nutrient uptake also appears to determine morphological responses. At sheltered sites, where leaf nutrient uptake is reduced by abundant periphyton and thick boundary layers, plants allocate more biomass to roots. At deep and wave-exposed sites, the absence of periphyton allows plants to take up nutrients through their leaves and allocation of biomass to shoots increases photosynthesis. 5 Overall, relative allocation to shoot and root biomass appears to be primarily controlled by nutrient availability, whereas allocation of available shoot biomass to particular structures is controlled by light availability.

  • 135.
    Strand, John A.
    et al.
    The Rural Economy and Agricultural Society of Halland, Lilla Boslid, Eldsberga, Sweden .
    Weisner, Stefan E.B.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Phenotypic plasticity – contrasting species-specific traits induced by identical environmental constraints2004In: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 163, no 3, p. 449-451Article in journal (Refereed)
    Abstract [en]

    Can it be assumed that a specific environmental constraint imposed on different species leads to a convergence in, for example, morphology? A phenotype expressed in response to external stimuli (e.g. size-reduction in response to mechanical stress) should be adaptive regardless of species – this is largely intuitive, but has been poorly studied. In this issue (pp. 651–660), Puijalon & Bornette reveal exciting new data that suggest that phenotypic plastic responses to identical environmental constraints may indeed be species-specific (Puijalon & Bornette, 2004).

  • 136.
    Suhling, Frank
    et al.
    Institut für Geoökologie, Technische Universität Braunschweig, Braunschweig, Germany .
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Gorb, Stanislav
    Spezielle Zoologie, Universität Kiel, Kiel, Germany .
    Kalkman, Vincent
    Nederlands Centrum voor Biodiversiteit Naturalis, Leiden, The Netherlands.
    Dijkstra, Klaas-Douwe
    Nederlands Centrum voor Biodiversiteit Naturalis, Leiden, The Netherlands.
    van Tol, Jan
    Nederlands Centrum voor Biodiversiteit Naturalis, Leiden, The Netherlands.
    Order Odonata2015In: Thorp and Covich's Freshwater Invertebrates: ecology and general biology / [ed] James H. Thorp & D. Christopher Rogers, Amsterdam: Academic Press, 2015, p. 894-932Chapter in book (Other academic)
    Abstract [en]

    This chapter introduces the insect order Odonata. It provides the most recent phylogeny and up-to-date systematics as well as genera and species numbers of the various families in the biogeographic regions. We also present an overview about the general biology, ecology and behavior of Odonata. This includes details on morphology and ultrastructures. We also attempt an updated categorization of odonate life cycle types. The subchapters on ecology and behavior focus on various aspects of habitat selection and microhabitat occupancy, including effects of biotic interactions and antipredation behavior. Finally, we summarize collection and sampling methods for adult and larval Odonata. © 2015 Elsevier Inc. All rights reserved

  • 137.
    Suhling, Frank
    et al.
    Dept. of Environ. System Analysis, Institut für Geoökologie, TU Braunschweig, Langer Kamp 19c, DE-38102 Braunschweig, Germany.
    Sahlén, Göran
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Ecology and Environmental Science.
    Kasperski, Judith
    Dept. of Environ. System Analysis, Institut für Geoökologie, TU Braunschweig, Langer Kamp 19c, DE-38102 Braunschweig, Germany.
    Gaedecke, Dunja
    Dept. of Environ. System Analysis, Institut für Geoökologie, TU Braunschweig, Langer Kamp 19c, DE-38102 Braunschweig, Germany.
    Behavioural and life history traits in temporary and perennial waters: comparisons among three pairs of sibling dragonfly species2005In: Oikos, ISSN 0030-1299, E-ISSN 1600-0706, Vol. 108, no 3, p. 609-617Article in journal (Refereed)
    Abstract [en]

    Identifying and examining traits that influence the distribution of species is crucial to the understanding of community structure. Theory predicts that traits should differ between species that live in temporary and permanent waters because of differing major environmental variables; viz drying out and predator presence, respectively. Species, however, will also be influenced by their evolutionary history, i.e. by the traits of their common ancestors. We studied differences in life history and behaviour traits in a series of laboratory experiments using pairs of dragonfly species out of three genera of Namibian Libellulidae (Odonata) with one species from each type of habitat. As predicted, growth rates were significantly higher in the temporary water species compared to the permanent water species. Activity and foraging, in contrast, differed between the genera, but did not differ between the habitat types. Hence, our study implies that the behavioural traits are influenced by phylogenetic inertia rather than by the habitat variables, while growth rate is adapted to the habitat. We argue that in all three genera one species has diverged recently from a sister species that lives in the original habitat of the genus, which may be temporary waters in Crocothemis Brauer and in Orthetrum Newman, and permanent waters in Trithemis Brauer. The behavioural traits may therefore be less well adapted. Rapid growth may be the more relevant trait because it is crucial to survival in temporary waters.

  • 138.
    Suhling, Frank
    et al.
    Institut für Geoökologie, Technische Universität Braunschweig, Langer Kamp 19c, D-38106 Braunschweig, Germany.
    Sahlén, Göran
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Ecology and Environmental Science.
    Martens, Andreas
    Biology, Karlsruhe University of Education, Bismarckstrasse 10, D-76133 Karlsruhe, Germany.
    Marais, Eugene
    National Museum of Namibia, Windhoek, P.O. Box 1203, Windhoek, Namibia.
    Schütte, Carsten
    Institut für Geoökologie, Technische Universität Braunschweig, Langer Kamp 19c, D-38106 Braunschweig, Germany.
    Dragonfly Assemblages in Arid Tropical Environments: A Case Study from Western Namibia2006In: Biodiversity and Conservation, ISSN 0960-3115, E-ISSN 1572-9710, Vol. 15, no 1, p. 311-332Article in journal (Refereed)
    Abstract [en]

    Dragonflies have been proposed as indicators for the ecosystem health of freshwater wetlands. For their useful functioning as indicators it is, however, necessary to identify species compositions in specific habitats and species-habitat associations, particularly in the tropics, where such knowledge is still weak. We examined the dragonfly species composition of 133 localities in the arid environment of western Namibia. An analysis of nestedness indicated that distinct, and predictable patterns of species associations can be expected. Discriminant analyses revealed that most of the nine habitat types separated by structural and hydrological parameters are well discriminated by their dragonfly assemblages. Spring brooks in particular host a specific assemblage, which is threatened due to the habitat restriction of several species, as well as by recent habitat loss and degradation. Using a hierarchical method of several criteria we demonstrated the selection of a set of potential indicator species from the species set, most of these being useful indicators for spring brook assemblages. The conservation status of certain habitats and species is discussed. We propose that dragonflies will have a high indicator potential for threatened freshwater wetlands in such areas and may also serve as an indication of the sustainable use of water resources including evaluating measures to rehabilitate environments.

  • 139.
    Suhling, Frank
    et al.
    Technische Universität Braunschweig.
    Suhling, Ida
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    Richter, Otto
    Environmental System Analysis, Institute of Geoecology, Braunschweig University of Technology.
    Rising temperatures, altered life cycles and their consequences for dragonflies in Europe2010Conference paper (Other academic)
    Abstract [en]

    Besides range expansion, altered life cycle patterns are the most visible signal of dragonfly responses to recent climate change. Since dragonflies are poikilotherm organisms their metabolism is directly responding to the ambient temperature. Thus, rising temperatures, which have already been recorded and are predicted to be even more severe in the future, should lead to alterations in all aspects of dragonfly life cycles. This may lead to temporal mismatches with other environmental variables relevant for the survival of dragonfly populations. The aim of our contribution is reviewing the known facts about temperature on growth rates and voltinism. We investigated temperature response of growth by laboratory experiments mainly in Libellulidae. Physiological structured mathematical models were used to simulate life cycle duration with various types of seasonal regulation. We will try predictions of consequences of rising temperatures for voltinism and phenology of some European dragonflies in future considering the regionally different climatic conditions. With the aid of such models we will also stress the question how temperature as environmental factor may influence present and future distribution of species in Europe.

  • 140.
    Suhling, Ida
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS). Technische Universität Braunschweig, Braunschweig, Germany.
    Suhling, Frank
    Technische Universität Braunschweig, Braunschweig, Germany.
    Thermal adaptation affects interactions between a range-expanding and a native odonate species2013In: Freshwater Biology, ISSN 0046-5070, E-ISSN 1365-2427, Vol. 58, no 4, p. 705-714Article in journal (Refereed)
    Abstract [en]

    1.Increasing temperature and invading species may interact in their effects on communities. In this study, we investigated how rising temperatures alter larval interactions between a naturally range-expanding dragonfly, Crocothemis erythraea, and a native northern European species, Leucorrhinia dubia. Initial studies revealed that C.erythraea grow up to 3.5 times faster than L.dubia at temperatures above 16 degrees C. As a result, we hypothesised that divergent temperature responses would lead to rapid size differences between coexisting larvae and, consequently, to asymmetric intraguild predation at higher ambient temperatures. 2. Mortality and growth rates were measured in interaction treatments (with both species present) and non-interaction controls (one species present) at four different temperature regimes: at an ambient temperature representative of central Germany, where both species overlap in distribution, and at temperatures increased by 2, 4 and 6 degrees C. 3.The mortality of C.erythraea did not differ between treatment and control. In contrast, mortality of L.dubia remained similar over all temperatures in the controls, but increased with temperature in the presence of the other species and was significantly higher there than in the controls. We concluded that L.dubia suffered asymmetric intraguild predation, particularly at increased temperature. Reduced growth rate of L.dubia in the interaction treatment at higher temperatures also suggested asymmetric competition for prey in the first phase of the experiment. 4.The results imply that the range expansion of C.erythraea may cause reduction in population size of syntopic L.dubia when temperature rises by more than 2 degrees C. The consequences for future range patterns, as well as other factors that may influence the interaction in nature, are discussed. © 2013 Blackwell Publishing Ltd.

  • 141.
    Svensson, Emma
    Halmstad University, School of Business, Engineering and Science.
    Humlors (Bombus spp.) möjlighet till fortlevnad utmed vägkanter intill cykelleder i Halmstad med omnejd2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    There is an ongoing negative trend on pollinator abundance worldwide due to different threats that affect their health and living conditions, such as pathogens and parasites in combination with different types of habitat loss among other factors. In this study I investigate if road verges adjacent to cycle paths could be a suitable environment for bumblebees (Bombus spp.) to thrive. 13 sites were sampled to find out what kind of diversity of bumblebees and flowering plants this type of habitat could hold by observing different aspects, e.g. shade and vegetation coverage together with species diversity and abundance. The results showed that shade coverage had an effect on the flower diversity at the sites and also that bumblebee species diversity as well as bumblebee abundance got affected by the diversity of flowers.

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  • 142.
    Svensson, Jonas
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Fleischer, Siegfried
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Rosenqvist, Torsten
    Halmstad University.
    Stibe, Lars
    Länsstyrelsen Halland.
    Pansar, Joakim
    Halmstad University.
    Ekologisk dagvattenhantering i Halmstad2002Book (Other academic)
    Abstract [en]

    The report compiles experiences with open stormwater treatment facilities at the City of Halmstad. In specific wetlands, research efforts are demonstrated that investigate retention effects of metals, nutrients and other substances.

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  • 143.
    Svensson, Ofir
    Halmstad University, School of Business and Engineering (SET).
    Does small-scale land use affect the understory birds negative in the Peruvian National Reserve Allpahuayo Mishana?2014Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Human activities that lead to fragmentation and habitat loss are big problems in the world. Due to global climate change the negative effects of fragmented habitats can be catastrophic for many organisms. In the Amazon rainforest, that is most sensitive to human impact, stands a big risk to lose its species diversity. Fragmentation and climate change together seems to escalate the death rate of rainforest plants and that will change the whole ecosystem. Birds and insects are depending on the trees and the trees faces big challenges now. Many of the rainforest organisms have been noticed to emigrate further up to northern altitudes due to the warmer climate and maybe also because of deforestation. Many of the lowland forest birds are predicted to distribute from their origin habitats. The national reserve Allpahuayo Mishana in the Peruvian Amazon is known for its diversity of birds. It is a big challenge for the reserve to maintain the origin forest composition from climate change, which will lead to losses of species. The reserve allows the local community to utilize the land for small-scale uses inside the protected zone. Many of the birds are sensitive for external disturbance. Most human activities are resulting in that the forest becomes less dense, which can lead to that the territory for the birds decreases. This makes it important for the reserve to improve the human land use not to restrict the birds' habitat inside the reserve. This project will investigate if the small-scale land uses affects the understory birds’ diversity and habitat negative. The purpose is to see if the fragmented forests in the reserve, closest to the utilized land, can functioning as a secondary forest for the understory birds, or are the understory birds limited by the small-scale land use, in the national reserve Allpahuayo Mishana? Four sites with various human activities were chosen to investigate if the sites contain any understory birds. The result showed that the most disturbed sites had poor bird diversity compare to the sites with no human disturbance.

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  • 144.
    Teneberg, Susanne
    et al.
    Halmstad University, School of Information Technology. Institute of Medical Biochemistry, Göteborg University, P. O. Box 440, SE 405 30 Göteborg, Sweden.
    Leonardsson, I.
    Department of Clinical Microbiology and Immunology, Örebro Medical Centre Hospital, SE 701 85 Örebro, Sweden.
    Karlsson, H.
    Department of General Surgery, Örebro Medical Centre Hospital, SE 701 85 Örebro, Sweden.
    Jovall, P.-A.
    Department of Medical Microbiology, Dermatology, and Infection, University of Lund, SE 223 62 Lund, Sweden.
    Ångström, J.
    Institute of Medical Biochemistry, Göteborg University, P. O. Box 440, SE 405 30 Göteborg, Sweden.
    Danielsson, D.
    Institute of Medical Biochemistry, Göteborg University, P. O. Box 440, SE 405 30 Göteborg, Sweden.
    Näslund, I.
    Institute of Medical Biochemistry, Göteborg University, P. O. Box 440, SE 405 30 Göteborg, Sweden.
    Ljungh, A.
    Institute of Medical Biochemistry, Göteborg University, P. O. Box 440, SE 405 30 Göteborg, Sweden.
    Wadström, T.
    Institute of Medical Biochemistry, Göteborg University, P. O. Box 440, SE 405 30 Göteborg, Sweden.
    Karlsson, K.-A
    Institute of Medical Biochemistry, Göteborg University, P. O. Box 440, SE 405 30 Göteborg, Sweden.
    Lactotetraosylceramide, a novel glycosphingolipid receptor for Helicobacter pylori, present in human gastric epithelium2002In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 277, no 22, p. 19709-19719Article in journal (Refereed)
    Abstract [en]

    The binding of Helicobacterpylori to glycosphingolipids was examined by binding of 35S-labeled bacteria to glycosphingolipids on thin-layer chromatograms. In addition to previously reported binding specificities, a selective binding to a non-acid tetraglycosylceramide of human meconium was found. This H. pylori binding glycosphingolipid was isolated and, on the basis of mass spectrometry, proton NMR spectroscopy, and degradation studies, were identified as Galβ3GlcNAcβ3-Galβ4Glcβ1Cer (lactotetraosylceramide). When using non-acid glycosphingolipid preparations from human gastric epithelial cells, an identical binding of H. pylori to the tetraglycosylceramide interval was obtained in one of seven samples. Evidence for the presence of lactotetraosylceramide in the binding-active interval was obtained by proton NMR spectroscopy of intact glycosphingolipids and by gas chromatography-electron ionization mass spectrometry of permethylated tetrasaccharides obtained by ceramide glycanase hydrolysis. The lactotetraosylceramide binding property was detected in 65 of 74 H. pylori isolates (88%) Binding of H. pylori to lactotetraosylceramide on thin-layer chromatograms was inhibited by preincubation with lactotetraose but not with lactose. Removal of the terminal galactose of lactotetraosylceramide by galactosidase hydrolysis abolished the binding as did hydrazinolysis of the acetamido group of the N-acetylglucosamine. Therefore, Galβ3GlcNAc is an essential part of the binding epitope.

  • 145.
    Thiere, Geraldine
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Biodiversity and ecosystem functioning in created agricultural wetlands2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This doctoral dissertation was produced in a cooperation between Halmstad University (Wetland Research Centre, School of Business and Engineering) and Lund University (Limnology & Marine Biology, Department of Ecology).

    Abstract . Wetland creation at large, regional scales is implemented as a measure to abate the biodiversity loss in agricultural landscapes and the eutrophication of watersheds and coastal areas by non-point source nutrient pollution (mainly nitrogen). The consequences of creating many new wetlands for biodiversity conservation and nutrient reten- tion (ecosystem functioning) in agricultural landscapes are still relatively unknown, both on local (per wetland) and regional (per landscape) scales. In Sweden, wetland creation has progressed already since the 1990s, and by now larger numbers of created wetlands are present, mainly in the intensively farmed landscapes of southwestern Sweden. This thesis aimed to investigate the following aspects in these systems: (i) their large-scale effects on biodiversity, (ii) their functional diversity of bacterial denitrifiers, (iii) the abiotic and biotic influences on wetland ecosystem functioning, (iv) the potential for biodiversity-function links, and (v) the potential for functional links and joint functioning.(i) Created wetlands hosted diverse assemblages of macroinvertebrates and plants. They maintained a similar com- position and diversity as natural ponds in agricultural landscapes. The environmental conditions per wetland did hardly affect macroinvertebrate and plant assemblages, and the prerequisites for nutrient retention did neither. In landscapes were wetland creation efforts had increased the total density of small water bodies by more than 30%, macroinver- tebrate diversity of created wetlands was facilitated on both local and regional scales. (ii) Diverse communities of denitrifying bacteria with the capacity for conducting different denitrification steps (functional types) were present in all investigated wetlands. The richness of denitrifying bacteria communities was affected by nitrate concentration and hydraulic loading rate, which may potentially be relevant for the nitrogen retention function of created wetlands. The diversity across different functional types of bacterial denitrifiers increased with nitrate concentration. (iii) Both abiotic and biotic factors influenced ecosystem functions of created wetlands. Variation in nitrogen retention was associated to nitrate load, but even to vegetation parameters. In wetlands with constant nitrate load, planted emergent vegetation facilitated nitrogen retention compared to other vegetation types. In wetlands with variable loads, nitrogen retention was facilitated if nitrate load was high and many different vegetation types were present; nitrogen load could explain the majority of the variation in nitrogen retention compared to vegetation parameters. Phosporus retention of created wetlands was best explained by vegetation parameters. Litter decomposition was inhibited at high nitrate to phosphorus ratios. Methane production increased with age and decreased with plant cover. (iv) Biodiversity may facilitate wetland ecosystem functions, particularly in dynamic wetland ecosystems. Nitrogen retention increased with vegetation type diversity, phosphorus retention capacity with plant richness, and litter decomposition with macroinvertebrate diversity. (v) Created wetlands have the capacity of sustaining several parallel ecosystem services. Some wetland functions were coupled; nitrogen retention increased with fast litter decomposition. On the other hand, methane emission and nitro- gen retention were independent of each other, as were nitrogen and phosphorus retention.In conclusion, created wetlands have the potential to at least partly abate the lost biodiversity and multifunctionality caused by the past extensive destruction of natural wetlands in agricultural landscapes.

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  • 146.
    Thulin, Charlotta
    et al.
    Halmstad University, School of Education, Humanities and Social Science.
    Taman, Nadia
    Halmstad University, School of Education, Humanities and Social Science.
    Utomhusundervisning i ämnet biologi: Utomhusmiljöns hinder och möjligheter i relation till elevers lärande i grundskolan2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
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  • 147.
    Tonderski, Karin
    et al.
    IFM, Linköpings Universitet.
    Weisner, Stefan E. B.Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.Landin, JanIFM, Linköpings Universitet.Oscarsson, HansMiljöskyddsenheten, Länsstyrelsen Västra Götaland.
    Våtmarksboken: Skapande och nyttjande av värdefulla våtmarker2002Collection (editor) (Other (popular science, discussion, etc.))
  • 148.
    Troast, Daniel
    et al.
    Department of Biology, Rutgers University, Newark, New Jersey, United States of America.
    Suhling, Frank
    Institut für Geoökologie, Technische Universität Braunschweig, Braunschweig, Germany.
    Jinguji, Hiroshi
    School of Food, Agricultural and Environmental Sciences, Miyagi University, Miyagi, Japan.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Ware, Jessica
    Department of Biology, Rutgers University, Newark, New Jersey, United States of America.
    A Global Population Genetic Study of Pantala flavescens2016In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, no 3, article id e0148949Article in journal (Refereed)
    Abstract [en]

    Among terrestrial arthropods, the dragonfly species Pantala flavescens is remarkable due to their nearly global distribution and extensive migratory ranges; the largest of any known insect. Capable of migrating across oceans, the potential for high rates of gene flow among geographically distant populations is significant. It has been hypothesized that P. flavescens may be a global panmictic population but no sufficient genetic evidence has been collected thus far. Through a population genetic analysis of P. flavescens samples from North America, South America, and Asia, the current study aimed to examine the extent at which gene flow is occurring on a global scale and discusses the implications of the genetic patterns we uncovered on population structure and genetic diversity of the species. This was accomplished using PCR-amplified cytochrome oxidase one (CO1) mitochondrial DNA data to reconstruct phylogenetic trees, a haplotype network, and perform molecular variance analyses. Our results suggested high rates of gene flow are occurring among all included geographic regions; providing the first significant evidence that Pantala flavescens should be considered a global panmictic population. © 2016 Troast et al.

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  • 149.
    törnqvist, sofia
    Halmstad University, School of Business, Engineering and Science.
    Skötsel av tätortsnära natur: Skötselplan för Ollonstupet2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The urban areas in the world continues to increase, cities becomes denser at the same time as they’re expanding. The nature found in the urban environments is important, both for its biodiversity and the services it provides for humans. To preserve and promote green spaces in the city is important. This is done largely by incorporating the urban nature in politics and city-planning. It is also done by more practical managementmeasures in the field, which are favourable for the urban nature. These measures vary depending on the nature values you want to promote and preserve. In Borås municipality the park management is responsible for the management of the municipality's natural areas. However, there are a lack of guidance and advice on how some of these areas can be managed. The aim of this work has therefore been to developa management plan for one of these urban nature areas. The area in question;Ollonstupet, is one of the most highly classified nature areas in the city of Borås. Various management measures, targets and guidelines are proposed, based on the nature- and recreational-values in the area. The basis for the management plan has been developed through field work, as well as previous inventories and assessments of biodiversity values.

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    Skötsel av tätortsnära natur
  • 150.
    Urrutia-Cordero, Pablo
    et al.
    Halmstad University, School of Business, Engineering and Science. Univ Autonoma Madrid, Dept Biol, Madrid 28049, Spain..
    Agha, Ramsy
    Univ Autonoma Madrid, Dept Biol, Madrid 28049, Spain..
    Cires, Samuel
    Univ Autonoma Madrid, Dept Biol, Madrid 28049, Spain..
    Angeles Lezcano, Maria
    Univ Autonoma Madrid, Dept Biol, Madrid 28049, Spain..
    Sanchez-Contreras, Maria
    Univ Autonoma Madrid, Dept Biol, Madrid 28049, Spain..
    Waara, Karl-Otto
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Utkilen, Hans
    Norwegian Inst Publ Hlth, Dept Water Hyg, N-0403 Oslo, Norway..
    Quesada, Antonio
    Univ Autonoma Madrid, Dept Biol, Madrid 28049, Spain..
    Effects of harmful cyanobacteria on the freshwater pathogenic free-living amoeba Acanthamoeba castellanii2013In: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 130, p. 9-17Article in journal (Refereed)
    Abstract [en]

    Grazing is a major regulating factor in cyanobacterial population dynamics and, subsequently, considerable effort has been spent on investigating the effects of cyanotoxins on major metazoan grazers. However, protozoan grazers such as free-living amoebae can also feed efficiently on cyanobacteria, while simultaneously posing a major threat for public health as parasites of humans and potential reservoirs of opportunistic pathogens. In this study, we conducted several experiments in which the freshwater amoeba Acanthamoeba castellanii was exposed to pure microcystin-LR (MC-LR) and six cyanobacterial strains, three MC-producing strains (MC-LR, MC-RR, MC-YR, MC-WR, [Dha7] MC-RR) and three strains containing other oligopeptides such as anabaenopeptins and cyanopeptolins. Although the exposure to high concentrations of pure MC-LR yielded no effects on amoeba, all MC-producing strains inflicted high mortality rates on amoeba populations, suggesting that toxic effects must be mediated through the ingestion of toxic cells. Interestingly, an anabaenopeptin-producing strain caused the greatest inhibition of amoeba growth, indicating that toxic bioactive compounds other than MCs are of great importance for amoebae grazers. Confocal scanning microscopy revealed different alterations in amoeba cytoskeleton integrity and as such, the observed declines in amoeba densities could have indeed been caused via a cascade of cellular events primarily triggered by oligopeptides with protein-phosphatase inhibition capabilities such as MCs or anabaenopeptins. Moreover, inducible-defense mechanisms such as the egestion of toxic, MC-producing cyanobacterial cells and the increase of resting stages (encystation) in amoebae co-cultivated with all cyanobacterial strains were observed in our experiments. Consequently, cyanobacterial strains showed different susceptibilities to amoeba grazing which were possibly influenced by the potentiality of their toxic secondary metabolites. Hence, this study shows the importance of cyanobacterial toxicity against amoeba grazing and, that cyanobacteria may contain a wide range of chemical compounds capable of negatively affect free-living, herbivorous amoebae. Moreover, this is of high importance for understanding the interactions and population dynamics of such organisms in aquatic ecosystems. (c) 2012 Elsevier B.V. All rights reserved.

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