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1.	2018 Ingår i: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 58:1 Forskningsöversikt (refereegranskat)
2.	Bombarda, F., et al. (författare) Runaway electron beam control 2019 Ingår i: Plasma Physics and Controlled Fusion. - : IOP Publishing. - 1361-6587 .- 0741-3335. ; 61:1 Tidskriftsartikel (refereegranskat)
3.	Labit, B., et al. (författare) Dependence on plasma shape and plasma fueling for small edge-localized mode regimes in TCV and ASDEX Upgrade 2019 Ingår i: Nuclear Fusion. - : IOP Publishing. - 1741-4326 .- 0029-5515. ; 59:8 Tidskriftsartikel (refereegranskat)abstract © 2019 Institute of Physics Publishing. All rights reserved. Within the EUROfusion MST1 work package, a series of experiments has been conducted on AUG and TCV devices to disentangle the role of plasma fueling and plasma shape for the onset of small ELM regimes. On both devices, small ELM regimes with high confinement are achieved if and only if two conditions are fulfilled at the same time. Firstly, the plasma density at the separatrix must be large enough (ne,sep/nG ∼ 0.3), leading to a pressure profile flattening at the separatrix, which stabilizes type-I ELMs. Secondly, the magnetic configuration has to be close to a double null (DN), leading to a reduction of the magnetic shear in the extreme vicinity of the separatrix. As a consequence, its stabilizing effect on ballooning modes is weakened.
4.	Broekman, Maarten J. E., et al. (författare) Evaluating expert-based habitat suitability information of terrestrial mammals with GPS-tracking data 2022 Ingår i: Global Ecology and Biogeography. - : Wiley. - 1466-822X .- 1466-8238. ; 31:8, s. 1526-1541 Tidskriftsartikel (refereegranskat)abstract Aim: Macroecological studies that require habitat suitability data for many species often derive this information from expert opinion. However, expert-based information is inherently subjective and thus prone to errors. The increasing availability of GPS tracking data offers opportunities to evaluate and supplement expert-based information with detailed empirical evidence. Here, we compared expert-based habitat suitability information from the International Union for Conservation of Nature (IUCN) with habitat suitability information derived from GPS-tracking data of 1,498 individuals from 49 mammal species.Location: Worldwide.Time period: 1998-2021.Major taxa studied: Forty-nine terrestrial mammal species.Methods: Using GPS data, we estimated two measures of habitat suitability for each individual animal: proportional habitat use (proportion of GPS locations within a habitat type), and selection ratio (habitat use relative to its availability). For each individual we then evaluated whether the GPS-based habitat suitability measures were in agreement with the IUCN data. To that end, we calculated the probability that the ranking of empirical habitat suitability measures was in agreement with IUCN's classification into suitable, marginal and unsuitable habitat types.Results: IUCN habitat suitability data were in accordance with the GPS data (> 95% probability of agreement) for 33 out of 49 species based on proportional habitat use estimates and for 25 out of 49 species based on selection ratios. In addition, 37 and 34 species had a > 50% probability of agreement based on proportional habitat use and selection ratios, respectively.Main conclusions: We show how GPS-tracking data can be used to evaluate IUCN habitat suitability data. Our findings indicate that for the majority of species included in this study, it is appropriate to use IUCN habitat suitability data in macroecological studies. Furthermore, we show that GPS-tracking data can be used to identify and prioritize species and habitat types for re-evaluation of IUCN habitat suitability data.
5.	Ekström, Johanna, et al. (författare) Diversity of human papillomaviruses in skin lesions 2013 Ingår i: Virology. - : Elsevier BV. - 0042-6822 .- 1096-0341. ; 447:1-2, s. 300-311 Tidskriftsartikel (refereegranskat)abstract Pools of frozen biopsies from patients with squamous cell carcinoma (SCC) (n=29) actinic keratosis (AK) (n=31), keratoacanthoma (n=91) and swab samples from 84 SCCs and 91 AKs were analysed with an extended HPV general primer PCR and high-throughput sequencing of amplimers. We found 273 different HPV isolates (87 known HPV types, 139 previously known HPV sequences (putative types) and 47 sequences from novel putative HPV types). Among the new sequences, five clustered in genus Betapapillomavirus and 42 in genus Gammapapillomavirus. Resequencing of the three pools between 21 to 70 times resulted in the detection of 283 different known or putative HPV types, with 156 different sequences found in only one of the pools. Type-specific PCRs for 37 putative types from an additional 296 patients found only two of these putative types. In conclusion, skin lesions contain a large diversity of HPV types, but most appeared to be rare infections. (C) 2013 Elsevier Inc. All rights reserved.
6.	Sorensen, Julie A, et al. (författare) Encouraging the installation of rollover protective structures in New York State : the design of a social marketing intervention. 2008 Ingår i: Scandinavian Journal of Public Health. - : SAGE Publications. - 1403-4948 .- 1651-1905. ; 36:8, s. 859-69 Tidskriftsartikel (refereegranskat)abstract AIMS: Increasing the percentage of rollover protective structure (ROPS) equipped tractors has been the focus of many agricultural safety campaigns. Traditionally efforts have attempted to persuade farmers through education or community awareness interventions. These efforts have lead to marginal change. In response, a social marketing approach was tested as a means for increasing interest in ROPS retrofitting in New York. METHODS: An initial phone survey was conducted with a random sample of New York farmers to identify a potential target population. Following target selection, in-depth interviews were conducted to isolate barriers and motivators to retrofitting. This information was used to develop message prototypes which were tested in small focus group discussions. Selected and revised messages, as well as various other incentives developed in response to feedback from interviews, were then tested in a prospective, quasi-randomized controlled trial. RESULTS: Small crop and livestock farms were selected as the intervention target since they represent 86% of New York farms with none or only one ROPS protected tractor. Barriers to retrofitting which were identified in interviews were: 1) constant exposures normalize risk, 2) risk is modeled by significant others and 3) safety in general and retrofitting in particular requires too much time and money. The piloting of ROPS incentives led to a marked increase in ROPS sales in New York. CONCLUSIONS: Social Marketing provides a promising framework for the design of agricultural injury prevention programs. The potential implications for other health initiatives seeking to promote behaviour change are also discussed.
7.	Strand, John A., et al. (författare) Anlagda våtmarker som flödesbuffrare : Hur skapar vi synergieffekter medbiologisk mångfald och pollinering? 2024 Rapport (övrigt vetenskapligt/konstnärligt)abstract Anlagda våtmarker har använts som naturbaserade lösningar på miljöproblem sedan 1990-talet i Sverige, framför allt i jordbrukslandskapet. Inledningsvis var huvudsyftet kostnadseffektiva åtgärder för att minska övergödningseffekter i havet men även våtmarkers positiva effekt på den biologiska mångfalden betonades tidigt. Under det senaste decenniet har anlagda våtmarker också diskuterats som lösning på andra miljönyttor, som flödesbuffring, vattenmagasinering och för att hålla kvar kol i organogena marker. För de senare ekosystemtjänsterna är forskningsläget emellertid osäkert och för vissa, såsom flödesbuffring, har det saknats faktiska mätdata. Denna brist är speciellt tydligt på de större landskapsskalor som behöver studeras för att exempelvis förstå våtmarkers och våtmarkslandskapens förmåga att förhindra översvämning lokalt och av nedströms belägna områden. I frånvaro av mätdata har förväntade positiva effekter i stället modellerats fram genom att utgå från parametrar som nederbörd och avrinningsområdens egenskaper. För att studera betydelsen av anlagda våtmarker i jordbrukslandskapet på flödesbuffring, dvs vattenmagasineringsförmågan, samt hur denna förmåga påverkar biologisk mångfald, har projektet samlat ett konsortium av experter och forskare inom framför allt ekologi och hydrologi. Inom ramen för projektet har en omfattande och strategisk provtagning genomförts under 3 år, av hydrologiska och ekologiska parametrar samt biologisk mångfald. Förutom dessa fältmätningar har även markägarnas åsikter kring värdet av sina anlagda våtmarker undersökts. Resultaten visar att anlagda våtmarker i jordbrukslandskapet har en stor potential att fungera som flödesutjämnare och buffra vatten både i den enskilda våtmarken och på landskapsnivå. Samtidigt gynnas en stor mängd organismgrupper, inklusive specialiserade våtmarksarter på nationella hotlistor. Resultaten visar också att för både flödesbuffring och biologisk mångfald finns flera avgörande parametrar vad gäller placering och design som styr hur väl en våtmark faktiskt levererar dessa ekosystemtjänster. De anlagda våtmarkerna i studien är huvudsakligen grävda dammar optimerade för näringsavskiljning och var därigenom relativt små och tog huvudsakligen emot dräneringsvatten från åkermark. Trots storleken bidrog de undersökta våtmarkerna till att dämpa högflöden med 3–17 %, vilket är i paritet med mätningar från naturliga våtmarker i tidigare studier (cirka 10 %). Det visade sig också att våtmarkerna bibehöll sina buffrande funktioner både under kortare högflödesperioder samt under ett år med hög årsnederbörd, vilket indikerar att de kan fungera med liknande effektivitet i ett framtida klimat med högre avrinning. Vid extremnederbörd framstår dock de buffrade volymerna i dessa små våtmarker som otillräckliga för att kunna fungera som (enskild) åtgärd, både idag och i framtiden. Till skillnad från naturliga våtmarker fanns inga starka samband mellan flödesbuffringen i studiens anlagda våtmarker och deras position i avrinningsområdet. Varken våtmarkens höjd över havet eller nerströms/uppströms placering i avrinningsområdet påverkade buffringsförmågan. Det fanns dock andra faktorer som påverkade våtmarkernas buffring, som att buffringen ökade med storleken på våtmarkens tillrinningsområden. Den effekten var delvis oväntad eftersom våtmarker med stora tillrinningsområde borde fyllas snabbare, vara fulla under längre tid och därmed buffra mindre effektivt. Resultaten tyder dock på att den tekniska utformningen på våtmarkerna ger dem god buffringskapacitet trots hög hydrologisk belastning. Resultaten visar också att det finns marginal för att förbättra buffringen genom tekniska anläggningsmekanismer, särskilt i fråga om tömningsmöjligheterna och reglerbarheten i utloppskonstruktionerna. Våra data visar att endast 47 % av den teoretiska volymförändringspotentialen utnyttjades i våtmarkerna, vilket kan medge ökad buffringspotential genom aktiv tömning/sänkning inför stora nederbördssituationer. De kraftiga vattennivåvariationerna i många av våtmarkerna, i kombination med förekomst av både flacka partier och brantare släntlutning, var positivt för artrikedomen hos flera organismgrupper. Generellt gynnades mångfalden hos flera grupper av större strandvåtmarker och flacka stränder, men det fanns undantag. Till exempel gynnades nätbyggande spindlar av brantare stränder. Ett oväntat resultat var också den begränsade eller till och med negativa effekten av betande djur, vilket går stick i stäv med rekommendationer i manualer för våtmarksanläggning och skötsel. Sannolikt gynnas leddjuren av att vegetationen hålls kort men samtidigt kan de rent fysiska effekterna av trampet missgynna artgrupper som har sin larvutveckling i blöt jord. För att förstå dessa samband behövs mer forskning som går in på mekanismer samt hur effekten påverkas av djurslag, djurtäthet och jordart. För insekter som utvecklas i vatten, som trollsländor, sågs inga samband med hydrologiska parametrar, men det var uppenbart att små, anlagda våtmarker är veritabla artöar för trollsländor. Totalt noterades 68 % av alla Sveriges arter på en yta (800 km2) som motsvarar 0,0015 % av Sveriges yta. Artsammansättning skilde sig mellan våtmarker och för att nå höga artantal på landskapsnivå kan det därför vara en fördel med många olika våtmarker i en region. För pollinatörer, särskilt bin, fanns korrelation mellan förekomst och storleken på våtmarkernas minsta vattenareal (dvs, när de är som mest uttorkade). Markägarenkäten visade att markägarna överlag ser mest nyttor, snarare än problem, med anlagda våtmarker. Mest notabelt var den höga nöjdheten med våtmarker (91 %) samt att en mycket stor andel markägare (83 %) använder sin våtmark för personlig rekreation, där skridskoåkning var populärast. Slutsatsen från studierna är att anlagda våtmarker som konstruerats för näringsavskiljning och i viss mån biologisk mångfald kan fungera bra som flödesbuffrare. Dessutom finns stor potential för ökad buffringskapacitet genom att både utformning (inte minst in- och utloppslösningar och aktiv nivåstyrning i våtmarkerna), läge och skötsel har en stor påverkan på den totala effekten. Dessutom verkar det finnas möjliga synergieffekter mellan vattennivåvariationer och artrikedomen av leddjur, men för att nå en hög biologisk mångfald i anlagda våtmarker bör stränderna vara heterogena eller att olika våtmarker har olika struktur.
8.	Zrinzo, Ludvic, et al. (författare) Targeting of the pedunculopontine nucleus by an MRI-guided approach : a cadaver study 2011 Ingår i: Journal of neural transmission. - Wien : Springer. - 0300-9564 .- 1435-1463. ; 118:10, s. 1487-1495 Tidskriftsartikel (refereegranskat)abstract Laboratory evidence suggests that the pedunculopontine nucleus (PPN) plays a central role in the initiation and maintenance of gait. Translational research has led to reports on deep brain stimulation (DBS) of the rostral brainstem in parkinsonian patients. However, initial clinical results appear to be rather variable. Possible factors include patient selection and the wide variability in anatomical location of implanted electrodes. Clinical studies on PPN DBS efficacy would, therefore, benefit from an accurate and reproducible method of stereotactic localization of the nucleus. The present study evaluates the anatomical accuracy of a specific protocol for MRI-guided stereotactic targeting of the PPN in a human cadaver. Imaging at 1.5 and 9.4 T confirmed electrode location in the intended region as defined anatomically by the surrounding fiber tracts. The spatial relations of each electrode track to the nucleus were explored by subsequent histological examination. This confirmed that the neuropil surrounding each electrode track contained scattered large neurons morphologically consistent with those of the subnucleus dissipatus and compactus of the PPN. The results support the accuracy of the described specific MR imaging protocol.
9.	Altai, M., et al. (författare) Re-188-Z(HER2 : V2), a promising targeting agent against HER2-expressing tumors: in vitro and in vivo assessment 2013 Ingår i: European Journal of Nuclear Medicine and Molecular Imaging. - 1619-7070 .- 1619-7089. ; 40, s. S119-S119 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
10.	Altai, M., et al. (författare) Selection of an optimal cysteine-containing peptide-based chelator for labeling of Affibody molecules with Re-188 2013 Ingår i: European Journal of Nuclear Medicine and Molecular Imaging. - 1619-7070 .- 1619-7089. ; 40, s. S219-S220 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
11.	Graversgaard, Morten, et al. (författare) Policies for wetlands implementation in Denmark and Sweden - historical lessons and emerging issues 2021 Ingår i: Land use policy. - : Elsevier. - 0264-8377 .- 1873-5754. ; 101 Tidskriftsartikel (refereegranskat)abstract Natural wetlands used to cover a significant part of the landscape, but these ecosystems have declined by >50% worldwide, and even more in Denmark and Sweden. However, since the 1980s, various policies have been implemented to restore and create wetlands. This study provides a comprehensive historical overview of policies used to stimulate the creation and restoration of wetlands in Denmark and Sweden, and also analyses what factors have facilitated participation or have been barriers for landowners. The analysis of wetlands implementation programmes in Denmark showed a change towards narrower focus on nitrogen reduction from 1998 and onwards, whereas policies in Sweden often have had a wider multifunctional purpose. In both countries, there has been a change in the compensation structure from a lump sum to annual payments, parallel to an observed increase in costs for wetlands implementation. There is still a large potential for recreating many more wetlands, and the national targets have not been reached in neither Denmark nor Sweden. Key success factors, for future wetlands implementation are sufficient compensation levels, flexible scheme designs and information-based strategies documenting relevant benefits and sustainability issues. In general, more advice and support from the state, regional and local participants, and farmers organisations, are required to increase the participation and achieve successful and cost-efficient wetlands implementation. A collaborative and catchment-based approach holds promise, where wetland governance can serve as a platform for collaboration between policy bodies and between farmers. Additionally, politicians and decision makers need to accept the area targets presented to them when setting policy goals for wetlands implementation, and to accept that restoring and constructing wetlands requires long implementation times before results can be demonstrated.
12.	Hambäck, Peter A., et al. (författare) Insekter och spindlar i anlagda våtmarker : Intressanta fynd från en systematisk undersökning i Uppland och södra Halland 2022 Ingår i: Entomologisk tidskrift. - 0013-886X. ; 143:1-2, s. 47-66 Tidskriftsartikel (refereegranskat)abstract Wetland area has decreased dramatically compared with preindustrial times, and in manyagricultural areas almost all wetlands have been drained to gain cropland. The trend hasin recent years been reversed because society has realized the many benefits of wetlandfunctions, such as for nutrient retention and flood control. In this study we inventoried 75 wetlands in Uppland and Halland for insects and spiders with Malaise traps, pitfall traps andsuction sampling. Most included wetlands are constructed, because the main purpose was toexamine if these wetlands also can be good for arthropod diversity, but we also included somemore natural wetlands as comparison. In total, we identified more than 25,000 individualsof more than 900 species of Coleoptera, Araneae, Diptera and Heteroptera. We found onenew species for Sweden, Hilara manicata Meigen 1822, and 37 new regional records. Alarge number of species found are considered threatened or else rare. Some wetlands closeto Mälaren were particularly interesting, with three species (Hypsosinga heri (Hahn 1831),Rhaphium antennatum (Charlier 1835) and Bagous robustus Brisout de Barneville 1863)that have no records nearby during recent times. These and other species found in the studyshow that constructed wetlands can provide good habitats for arthropod biodiversity andrare species, particularly if wetland shores are grazed and trampled by cattle.
13.	Joelsson, Arne, et al. (författare) The Aquarius approach on mitigation of phosphorus losses 2010 Ingår i: 6th International Phosphorus Workshop (IPW6). ; , s. 164- Konferensbidrag (övrigt vetenskapligt/konstnärligt)
14.	Nielsen, Wils, et al. (författare) OMERACT 2023 Systemic Lupus Erythematosus Special Interest Group : Winnowing and Binning Preliminary Candidate Domains for the Core Outcome Set 2024 Ingår i: Seminars in Arthritis & Rheumatism. - : Elsevier. - 0049-0172 .- 1532-866X. ; 65 Tidskriftsartikel (refereegranskat)abstract BACKGROUND: The Outcome Measures in Rheumatology (OMERACT) Systemic Lupus Erythematosus (SLE) Working Group held a Special Interest Group (SIG) at the OMERACT 2023 conference in Colorado Springs where SLE collaborators reviewed domain sub-themes generated through qualitative research and literature review.OBJECTIVE: The objective of the SIG and the subsequent meetings of the SLE Working Group was to begin the winnowing and binning of candidate domain sub-themes into a preliminary list of candidate domains that will proceed to the consensus Delphi exercise for the SLE COS.METHODS: Four breakout groups at the SLE SIG in Colorado Springs winnowed and binned 132 domain sub-themes into candidate domains, which was continued with a series of virtual meetings by an advisory group of SLE patient research partners (PRPs), members of the OMERACT SLE Working Group Steering Committee, and other collaborators.RESULTS: The 132 domain sub-themes were reduced to a preliminary list of 20 candidate domains based on their clinical and research relevance for clinical trials and research studies.CONCLUSION: A meaningful and substantial winnowing and binning of candidate domains for the SLE COS was achieved resulting in a preliminary list of 20 candidate domains.
15.	Strand, John A., et al. (författare) Combating eutrophication of the sea and enhancing biodiversity of the agricultural landscape : experiences from wetland creation in Sweden 2011 Konferensbidrag (övrigt vetenskapligt/konstnärligt)
16.	Strand, John A., et al. (författare) Dynamics of submerged macrophyte populations in response to biomanipulation 2001 Ingår i: Freshwater Biology. - Chichester, United Kingdom : Wiley-Blackwell. - 0046-5070 .- 1365-2427. ; 46:10, s. 1397-1408 Tidskriftsartikel (refereegranskat)abstract 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.
17.	Strand, John A., 1967-, et al. (författare) Effects of wetland construction on nitrogen transport and species richness in the agricultural landscape – experiences from Sweden 2013 Ingår i: Ecological Engineering. - Amsterdam : Elsevier. - 0925-8574 .- 1872-6992. ; 56, s. 14-25 Tidskriftsartikel (refereegranskat)abstract Constructed wetlands, have been used to decrease nitrogen transport from agricultural catchments to the coast of Sweden, while simultaneously contributing to increased species richness in the landscape. The purpose of this paper is to compile and evaluate data that have been produced in Sweden during some 20 years of using constructed wetlands as an environmental tool. To evaluate effects of different stated objectives for constructed wetlands within different national support systems we focus on nitrogen removal and bird and amphibian species richness. Continuous automatic water sampling for nitrogen removal measurements, during 1.5 to 10 years, has been performed in 7 constructed wetlands located in agricultural catchments in southern Sweden. Nitrogen removal per wetland area varied between wetlands but the results imply that an annual removal of at least 1000. kg. N per ha wetland area can be achieved in individual wetlands. Data from the long-term monitoring of the 7 wetlands, together with nitrogen removal data in the literature, were used to model >150 randomly selected constructed wetlands. According to the modeling, the nitrogen removal per created wetland area varied markedly between different wetland creation programs and was generally considerably lower compared to what can be achieved in individual wetlands. Cost-efficiency of nitrogen removal in wetland creation programs can be increased considerably with improved planning and if other desired benefits (e.g. species richness) contribute to share the costs for wetland creation. The effects of constructed wetlands in Sweden on species number and populations of wetland birds and amphibians were large enough to positively affect the occurrence of species in the national red list, i.e. on a national population level. Species richness of wetland breeding birds in the constructed wetlands were relatively stable after 13 years, but different functional groups had very different succession pattern. The mean maximum breeding bird species number in the wetlands occurred after 3.8 years. Wetland birds and amphibians colonized constructed wetlands irrespective of the original objective of the wetland (nitrogen removal or biodiversity). However, some amphibian species showed preference for biodiversity wetlands. There were clear effects of wetland construction on the regional populations of non-wetland bird species. The maximum species number for a given wetland size was found to be higher than previously reported. The analyses show that wetland construction can be a cost effective method for decreasing transport of diffuse pollution from arable land, and that the wetlands are important for the species numbers and population sizes on all spatial scales. © 2013 Elsevier B.V.
18.	Strand, John A., et al. (författare) Kävlingeåprojektet – utvärdering av etapp I-III : Rapport på uppdrag av Programberedningen för Kävlingeåprojektet 2010 Rapport (övrigt vetenskapligt/konstnärligt)
19.	Strand, John A., et al. (författare) Markägare som vattenförvaltare i ett förändrat klimat 2012 Rapport (övrigt vetenskapligt/konstnärligt)
20.	Strand, John A., et al. (författare) Morphological plastic responses to water depth and wave exposure in an aquatic plant (Myriophyllum spicatum) 2001 Ingår i: Journal of Ecology. - Oxford, United Kingdom : Wiley-Blackwell. - 0022-0477 .- 1365-2745. ; 89:2, s. 166-175 Tidskriftsartikel (refereegranskat)abstract 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.
21.	Strand, John A., et al. (författare) Phenotypic plasticity – contrasting species-specific traits induced by identical environmental constraints 2004 Ingår i: New Phytologist. - Oxford : Blackwell. - 0028-646X .- 1469-8137. ; 163:3, s. 449-451 Tidskriftsartikel (refereegranskat)abstract 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).
22.	Strand, John A (författare) Submerged macrophytes in shallow eutrophic lakes - regulating factors and ecosystem effects 1999 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract In this thesis I have studied factors that regulate submerged macrophyte abundance, morphology and distribution in shallow eutrophic lakes, and how submerged macrophytes may affect the ecosystem. Light attenuation through the water column (turbidity and water depth) is probably not the most important factor regulating the distribution of submerged vegetation in macrophyte dominated shallow eutrophic lakes, e.g. due to clear water and the plants capability of morphological responses. However, during plant establishment and re-colonisation of vegetation (natural or induced shifts between turbid and clear-water states) turbidity and water depth are likely to be of greater importance. It was also found that periphyton may be a ?double-edged sword? in shallow lake ecosystems. Increased nutrient uptake by periphyton due to increased available surface area, when submerged macrophytes are abundant, is an important mechanism stabilising the lake in a clear-water state. However, periphyton affect submerged macrophytes negatively, and wave exposure dependent periphyton growth might initiate shifts from clear-water to turbid states due to the loss of submerged vegetation at sheltered sites. Grazing by crayfish affected seedlings but not mature plants, indicating that plants can outgrow grazers, but also that the time of grazing (in the life-history of the plant) is important for the ecological implications. Waterfowl grazing was higher at sheltered sites and may also contribute to initiate shifts from clear-water to turbid states. Submerged macrophyte seed bank is highly variable within and between lakes, and the importance of the seed bank for the vegetation dynamics seems to vary depending on lake history, wave exposure and the species involved. Submerged macrophyte re-colonisation is important for successful biomanipulation. Important factors for re-colonisation are: sufficient Secchi depth improvment, lake morphometry, species composition of the remnant populations, and low grazing pressure. Viable seed banks do not seem to be necessary but are likely to increase the probability of re-colonisation, and diversity.
23.	Strand, John A., et al. (författare) Vegetationsförändringar i Vänern - steg två : Projektplan för att utreda orsaken till igenbuskningen av skär och stränder samt dynamik hos vattenvegetationen 2002 Rapport (övrigt vetenskapligt/konstnärligt)
24.	Strand, John A., et al. (författare) Wave exposure related growth of epiphyton : Implications for the distribution of submerged macrophytes in eutrophic lakes 1996 Ingår i: Hydrobiologia. - Dordrecht : Kluwer Academic Publishers. - 0018-8158 .- 1573-5117. ; 325:2, s. 113-119 Tidskriftsartikel (refereegranskat)abstract 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.
25.	Svensson, Jonas M., et al. (författare) Rikare mångfald och mindre kväve : Utvärdering av våtmarker skapade med stöd av lokala investeringsprogram och landsbygdsutvecklingsstöd 2004 Bok (övrigt vetenskapligt/konstnärligt)abstract På uppdrag av Naturvårdsverket och Jordbruksverket har Våtmarkscentrum, Högskolan i Halmstad, utvärderat svenska våtmarker anlagda med landsbygdsutvecklingsstöd, LBU-stöd (Miva, projektstöd och Lmiva utan projektstöd) respektive våtmarker anlagda inom lokala investeringsprogram (LIP) avseende näringsretention och biologisk mångfald. Resultaten från utvärderingen redovisas separat för de fyra olika grupperna/kategorierna av anlagda våtmarker enligt nedan (fetstil anger kategorihänvisning i text, tabeller och figurer):• Våtmarker anlagda med anläggningsstöd inom Lokala investeringsprogram 1998 - 2002, LIP.• Våtmarker anlagda med anläggningsstöd inom LBU-projektstöd (dessa våtmarker får vanligen även skötselstöd, Lmiva), 2000 - 2002.• Våtmarker anlagda 1996-1999, utan anläggningsstöd men med skötselstöd (Miljöstöd), Miva.• Våtmarker anlagda från år 2000 - , utan anläggningsstöd men med skötselstöd (LBU-våtmarker som endast får skötselersättning), Lmiva.Syftet har främst varit att utvärdera och jämföra hur våtmarksanläggning inom olika stödformer har bidragit till minskad övergödning och ökad biologisk mångfald. Syftet har alltså inte varit att utvärdera enskilda våtmarker utan att ge en helhetsbild för olika stödformer och regioner. Därför har det varit nödvändigt att basera utvärderingen på data för ett stort antal våtmarker. Detta innebär att utförliga mätningar ej kunnat genomföras inom de enskilda objekten. Närsaltsretention har därför beräknats baserat på modeller och biologisk mångfald har undersökts genom att trollsländor använts som indikatorgrupp.Inom uppdraget har, med jordbruksstöd, registrerats information om totalt 908 våtmarksobjekt om totalt 2860 ha ersatt yta fördelat på 1815 ha Miva, 920 ha projektstöd och 125 ha Lmiva utan projektstöd. Totalt registrerade våtmarker med stöd från LIP är 274 st, omfattande 439 ha.Kompletterande fältstudier har utförts i drygt 100 st våtmarker. Främst är det resultaten från dessa våtmarker som sammanfattas nedan...
26.	Vretare, Viveka, et al. (författare) Phenotypic plasticity in Phragmites australis as a functional response to water depth 2001 Ingår i: Aquatic Botany. - Amsterdam, Netherlands : Elsevier. - 0304-3770 .- 1879-1522. ; 69:2-4, s. 127-145 Tidskriftsartikel (refereegranskat)abstract We have performed investigations to see if the emergent macrophyte Phragmites australia (Cav.) Trin. ex Steud. exhibits phenotypic plasticity as a response to water depth and if such responses in biomass allocation pattern and morphology are functional responses, improving the performance of the plant. In greenhouse experiments plants were grown in deep or shallow water to evaluate plastic responses. Allometric methods were used to handle effects caused by size differences between treatments. To evaluate if phenotypic responses to water depth are functional, the relative growth rate (RGR) of plants acclimatised to shallow or deep water, respectively, were compared in deep water, and the growth of plants in fluctuating and constant water level were compared. When grown in deep (70 or 75 cm), compared to shallow (20 or 5 cm) water, plants allocated proportionally less to below-ground weight, made proportionally fewer but taller stems, and had rhizomes that were situated more superficially in the substrate. Plants acclimatised to shallow water had lower RGR than plants acclimatised to deep water, when they were grown in deep water, and plants in constant water depth (40 cm) grew faster than plants in fluctuating water depth (15/65 cm). In an additional field study, the rhizomes were situated superficially in the sediment in deep, compared to shallow water. We have shown that P. australis acclimatises to deep water with phenotypic plasticity through allocating more resources to stem weight, and also by producing fewer but taller stems, which will act to maintain a positive carbon balance and an effective gas exchange between aerial and below-ground parts. Furthermore, the decreased proportional allocation to below-ground parts probably results in decreased nutrient absorption, decreased anchorage in the sediment and decreased carbohydrate reserves. Thus, in deep water, plants have an increased risk of becoming uprooted and experience decreased growth and dispersal rates. (C) 2001 Elsevier Science B.V. All rights reserved.
27.	Weisner, Stefan, 1954-, et al. (författare) Combating eutrophication in Sweden : Importance of constructed wetlands in agricultural landscapes 2005 Ingår i: Is living water possible in agricultural areas?. - Ås, Norway : Jordforsk. - 8274675371 ; , s. 66-69 Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract The Wetland Centre at Halmstad University was commissioned by the Swedish Environmental Protection Agency and the Swedish Board of Agriculture to evaluate the effects of artificially created wetlands in Sweden between the years 1996 and 2002 with regard to nutrient retention and biodiversity. The creation of these wetlands has been financed either by Rural Development Support (RDS: Miva, Project support or Lmiva without Project support) or by Local Investment Programmes (LIP). The results are presented separately for the four different categories of constructed wetlands:Constructed wetlands financed by LIP (Local Investment Programmes) (1998-2002).Constructed wetlands financed by PS (Project Support) (2000-2002).Constructed wetlands financed by Miva (Restoration and Establishment of Wetlands and Ponds on Arable land and Semi-natural Grazing land) (1996-1999).Constructed wetlands financed by Lmiva (RDS wetlands that only get management support) (2000-2002).The main purpose of this study has been to evaluate the extent to which wetlands created by means of these different support systems have contributed to reduced eutrophication and increased biodiversity. The purpose has not been to evaluate individual wetlands but to give an overview of the differences in efficiency between the various support systems and, to some extent, the difference in results between various geographical regions within Sweden. It has therefore been necessary to include a large number of wetlands in the evaluation, which means that extensive field sampling in the individual wetlands has not been possible. The estimates concerning nutrient retention has therefore been based on modelling, and the biodiversity has been assessed by using dragonflies (Odonata) as indicator organisms.Information on 908 wetlands with a total area of 2860 hectares financed by RDS has been compiled and registered. In terms of area, these wetlands divide into 1815 ha financed by Miva, 920 ha financed by PS and 125 ha by Lmiva. In addition, 274 wetlands created by means of LIP, with a total area of 439 ha, have been registered. Field surveys and sampling has been conducted in more than 100 wetlands randomly selected from this register. It is mainly the results from these selected wetlands that are presented here.
28.	Weisner, Stefan E.B., et al. (författare) Combating eutrophication and biodiversity loss in Sweden : importance of constructed wetlands in the agricultural landscape 2007 Ingår i: Multifunctions of wetland systems. - Padua : PAN. - 9788890294808 ; , s. 60-61 Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract The results of this evaluation show that constructed wetlands in the agricultural landscape are capable of a substantial reduction of the nutrient transport to downstream recipients, but only if properly located. These wetlands will also contribute to an increased biodiversity even if not planned primarily for this purpose. The use of wetlands for multiple functions needs to be developed to motivate large-scale wetland construction.
29.	Weisner, Stefan E. B., et al. (författare) Ecology and management of plants in aquatic ecosystems 2002 Ingår i: Handbook of ecological restoration. - Cambridge : Cambridge University Press. - 0521791286 ; , s. 242-256 Bokkapitel (refereegranskat)abstract The central role of macrophytes for the functioning of aquatic systems means that the most effective way to manage these systems is often through vegetation management. For this we need to understand the mechanisms regulating vegetation distribution. Submerged macrophyte distribution is mainly related to water depth, water transparency and epiphytic growth. The distribution of emergent vegetation can largely be predicted from water depth and substrate characteristics. Also, in both submerged and emergent macrophytes, the effects on the vegetation of grazing can be dramatic. Management should aim at providing environmental conditions favouring the desired ecosystem state, rather than methods directly aimed at the vegetation. For example, the best method for promoting establishment of emergent vegetation is often lowering of the water level. To establish submerged vegetation, water transparency can be increased through biomanipulation (the removal of zooplanktivorous fish leading to increased zooplankton grazing pressure on phytoplankton). Changes in water depth and introduction of grazers are often effective measures to control growth of aquatic weeds.
30.	Weisner, Stefan E.B. 1954-, et al. (författare) Mechanisms regulating abundance of submerged vegetation in shallow eutrophic lakes 1997 Ingår i: Oecologia. - Heidelberg,Germany : Springer Berlin/Heidelberg. - 0029-8549 .- 1432-1939. ; 109:4, s. 592-599 Tidskriftsartikel (refereegranskat)abstract Shallow eutrophic lakes tend to be either in a turbid state dominated by phytoplankton or in a clear-water state dominated by submerged macrovegetation. Recent studies suggest that the low water turbidity in the clear-water state is maintained through direct and in-direct effects of the submerged vegetation. This study examined what mechanisms may cause a recession of the submerged vegetation in the clear-water state, and thereby a switch to the turbid state. The spatial distribution of submerged vegetation biomass was investigated in two shallow eutrophic lakes in the clear-water state in southern Sweden. Biomass of submerged vegetation was positively correlated with water depth and wave exposure, which also were mutually correlated, suggesting that mechanisms hampering submerged vegetation were strongest at shallow and/or sheltered locations. The growth of Myriophyllum spicatum, planted in the same substrate and at the same water depth, was compared between sheltered and wave exposed sites in two lakes. After 6 weeks the plants were significantly smaller at the sheltered sites, where periphyton production was about 5 times higher than at the exposed sites. Exclosure experiments were conducted to evaluate the effects of waterfowl grazing on macrophyte biomass. Potamogeton pectinatus growth was decreased by grazing, whereas M. spicatum was not affected. The effects were greater at a sheltered than at a wave-exposed site, and also negatively related to distance from the reed belt. These results suggest that competition from epiphytes and waterfowl grazing hamper the development of submerged vegetation at sheltered and/or shallow locations. An increased strength of these mechanisms may cause a recession of submerged vegetation in shallow eutrophic lakes in the clear-water state and thereby a switch to the turbid state.
31.	Weisner, Stefan, 1954-, et al. (författare) Rhizome architecture in Phragmites australis in relation to water depth : Implications for within-plant oxygen transport distances 1996 Ingår i: Folia Geobotanica. - Dordrecht : Springer Netherlands. - 1211-9520 .- 1874-9348. ; 31:1, s. 91-97 Tidskriftsartikel (refereegranskat)abstract Phragmites australis (CAV.) TRlN. ex STEUD. is a perennial plant, largely relying on its rhizomes for resource storage, spreading and anchorage in the substrate. Vertical distribution and length of horizontal rhizomes of Phragmites australis were investigated at the reed bed edge in a lake in southern Sweden. In deep water, horizontal rhizomes were relatively short and superficially situated in the substrate. It is hypothesised that this is an adaptation to water depth by keeping O-2-transport distances through shoots and rhizomes as short as possible. In shallow water, P. australis rhizomes generally penetrated deeply into the substrate, probably improving anchorage and nutrient uptake possibilities. Further, horizontal rhizomes were longer in shallow water, which may increase the rate of vegetative spread. Because of these changes in rhizome architecture, "critical within-plant oxygen transport distances" did not change with water depth. This indicates that P. australis maximises the extension of its rhizomes in relation to spatial differences in water depth. This may limit the ability of P. australis to tolerate sudden temporal increases in water depth or eutrophication.
32.	Åhlén, David, et al. (författare) Arthropod diversity in constructed wetlands is affected strongly by shoreline properties but only weakly by grazing 2024 Ingår i: Journal of Biogeography. - Chichester : Wiley-Blackwell. - 0305-0270 .- 1365-2699. Tidskriftsartikel (refereegranskat)abstract AimAquatic-terrestrial transition zones contain features essential for many species that often benefit wetland biodiversity. Shallow flood-zone areas and reed beds are indicative of natural wetland habitats; however, how such features affect the native arthropod biodiversity in constructed wetlands is scarcely investigated. We asked how these shoreline features, as well as wetland shoreline properties and grazing management, influence riparian arthropod diversities and habitat specializations.LocationConstructed wetlands, Sweden.TaxaAraneae, Coleoptera, Diptera.MethodsTaxonomic-, phylogenetic- and trait diversities, along with habitat specialist species richness, were measured in riparian spiders, beetles and selected Diptera in 68 constructed wetlands in two regions of Sweden. We ran structural equation models to estimate direct and indirect effects from shoreline slope, flooded grassland, reed areas and grazing management on group diversities, and used multivariate models to determine drivers on habitat specialist species richness.ResultsFlooded grassland and reed area, along with shoreline slope influenced arthropod diversities, and responses differed between arthropod groups and diversity metrics. Spider trait diversity was greater in wetlands with larger flooded grassland areas, whilst beetle trait diversity was reduced. Spider phylogenetic diversity was greater in wetlands containing larger reed areas and in wetlands with steeper shorelines. However, species richness in predatory flies was greater in wetlands with more gentle shorelines. Grazing management had limited effects on arthropod diversities; however, species richness in wetland specialist and generalist predatory dipterans was greater in the absence of grazers in wetlands with greater flooded grassland areas.Main ConclusionsAs requirements vary considerably among arthropods, care must be taken when constructing and managing wetlands to benefit arthropod biodiversity. The present results suggest wetlands with a varied shoreline, albeit with greater proportions of flood areas, or multiple adjacent wetlands with varying shores in a wet landscape and a mild grazing regiment, would accommodate a more diverse arthropod fauna. © 2024 The Author(s). Journal of Biogeography published by John Wiley & Sons Ltd.

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