One of the ways in which plants are responding to climate change is by shifting their ranges to higher elevations. Early life‐history stages are major bottlenecks for species' range shifts, and ...variation in seedling emergence and establishment success can therefore be important determinants of species' ability to establish at higher elevations. Previous studies have found that warming per se tends to not only increase seedling establishment in alpine climates but it also increases plant productivity, which could limit establishment success through increased competition for light. Here we disentangle the relative importance of several climate‐related abiotic and biotic factors on sub‐alpine species' seedling emergence and survival in the alpine. Specifically, we test how temperature, precipitation and competition from neighbouring vegetation impacts establishment, and also whether species' functional traits, or strategies impact their ability to colonise alpine locations. We found that our six sub‐alpine study species were all able to recruit from seed in alpine locations under the extant alpine climate, but their emergence was limited by competition from neighbouring vegetation. This indicates that biotic interactions can hinder the range shifts expected as a result of climate warming. Species with a resource conservative strategy had higher emergence in the extant alpine climate than species with a resource acquisitive strategy, and they were largely unaffected by changes in temperature. The resource acquisitive species, in contrast, had faster emergence under warming, especially when they were released from competition from neighbouring vegetation. Our results indicate that competition from the established vegetation is limiting the spread of lowland species into the alpine, and as the climate continues to warm, species with resource acquisitive traits might gain an advantage.
Plants are responding to climate change by shifting their ranges to higher elevations. There is a large variety in how fast and how far species spread, and we do not understand the factors that allow or restrict subalpine species from colonising new alpine locations. To explore the relative importance of abiotic and biotic factors, as well as species‐specific life strategies, on these limitations, we performed a seed transplant experiment with and without experimental warming, crossed with manipulation of biotic interactions, replicated across a precipitation gradient, with three resource conservative and three resource acquisitive subalpine species.
Abstract
Plant removal experiments allow assessment of the role of biotic interactions among species or functional groups in community assembly and ecosystem functioning. When replicated along ...climate gradients, they can assess changes in interactions among species or functional groups with climate. Across twelve sites in the Vestland Climate Grid (VCG) spanning 4 °C in growing season temperature and 2000 mm in mean annual precipitation across boreal and alpine regions of Western Norway, we conducted a fully factorial plant functional group removal experiment (graminoids, forbs, bryophytes). Over six years, we recorded biomass removed, soil microclimate, plant community composition and structure, seedling recruitment, ecosystem carbon fluxes, and reflectance in 384 experimental and control plots. The dataset consists of 5,412 biomass records, 360 species-level biomass records, 1,084,970 soil temperature records, 4,771 soil moisture records, 17,181 plant records covering 206 taxa, 16,656 seedling records, 3,696 ecosystem carbon flux measurements, and 1,244 reflectance measurements. The data can be combined with longer-term climate data and plant population, community, ecosystem, and functional trait data collected within the VCG.
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Lumpfish (Cyclopterus lumpus L.) in Norway is currently produced in traditional flow-through systems (FTS). Hatcheries frequently show signs of bacterial infections, unstable microbial communities in ...the rearing water and varying mortality. Recirculating aquaculture systems (RAS) is proposed to create stable and healthy microbial environments, with less probabilities for blooming of opportunistic microbes. Studies have also shown that RAS increases the survival of marine fish. The aim with this study was to investigate the effect of various RAS water treatment designs on water and biofilm microbiota, survival, growth and gill health of lumpfish. An experiment with lumpfish was conducted, from 2 months post hatch to the transfer into sea cages. Five different water treatment regimens were compared: 1. RAS with no additional water treatment, 2. RAS with a filtration unit for removal of small particles, 3. RAS with filtration and disinfection with UV-irradiation, 4. RAS with filtration and disinfection with UV-irradiation and ozone and 5. FTS as a reference. The microbiota of the rearing water and tank wall biofilm were sampled and characterized by Illumina sequencing of 16S rDNA amplicons. Lumpfish juveniles reared in the RAS treatments were exposed to a more stable and diverse rearing water microbiota, with a lower share of opportunistic bacteria, a probable reason for the higher survival and better gill health of the fish compared to siblings reared in the FTS. Lumpfish reared in RAS without disinfection were exposed to a more diverse and stable water microbiota, with a lower share of opportunistic and potential harmful bacteria, compared to the lumpfish reared in RAS with disinfection and FTS. This resulted in better gill health. Fish in RAS with filtration, but no disinfection, had a better gill health than the fish in the RAS without filtration, possibly due to the reduction of small particles. The lumpfish were exposed to different microbial communities of both water and biofilm, due to the different treatments of the incoming tank water. In conclusion, our results indicate that implementation of RAS in the production of lumpfish has a potential to increase both survival, growth and gill health of the fish and that RAS with filtration of small particles, but without disinfection, result in the best fish health and performance among the investigated treatments.
•We managed to increase survival, growth and health of lumpfish by implementing RAS.•Disinfection in the RAS loop affected the microbiota and the gill health negatively.•Filtration of small particles improved gill health of lumpfish.
Recirculating aquaculture systems (RAS) harbour complex microbial communities which can have an impact on the growth and development of the reared fish. This study aimed to improve our understanding ...of microbial community dynamics in a RAS involving three production batches of Atlantic salmon fry and parr during a period of 20 months. Water for analysis of microbiota was sampled at different positions in the RAS, and we also examined the effect of UV treatment on the water microbiota. Microbial communities were characterized by 16S rDNA amplicon sequencing of water samples taken directly upstream and downstream of the UV treatment unit and from three of the rearing tanks. In total 6 sampling events were made during a 20-month period. The study showed that: 1) Two of the production batches had a highly similar water microbiota despite disinfection of the system between the batches and rearing fish of different stages. In contrast, the first production batch showed a different water microbiota with variable composition through the system and over time. A more immature biofilter in the first batch may explain these differences. 2) The full-flow UV treatment directly upstream the rearing tanks had no observable effect on the community composition of the water microbiota in the different sampling positions in the RAS. This was likely a consequence of the low hydraulic retention time (HRT) (23 min) in rearing tanks, low bacterial regrowth in the fish tanks and community changes throughout the RAS loop. 3) The disinfection effect on viable bacterial densities in the water directly downstream of the UV treatment was around 89%, when the water was clear. Regrowth of bacteria following disinfection was low compared to those reported for marine RAS with UV disinfection and long HRT in fish tanks. The study shows that UV disinfection can be used to efficiently reduce bacterial density without compromising the microbial water quality in the fish tanks in RAS with low HRT.
•Production batches with mature biofilters had a highly similar water microbiota despite system disinfection and rearing fish of different stages.•The full-flow UV treatment had no observable effect on the water community composition throughout the RAS.•The UV treatment reduced the culturable bacterial numbers with 89% and regrowth in fish tanks was low compared to marine hatcheries.
The microbiota of recirculating aquaculture systems (RAS) is of major importance for optimal fish health. However, the microbial communities in commercial RAS are highly complex and more knowledge is ...needed to potentially control and maintain beneficial microbial communities for good fish production. In this study we monitored microbial communities in a commercial RAS producing Atlantic salmon fry (Salmo salar) during seven consecutive production batches. The water of rearing tanks and the water sump downstream of the biofilter/upstream of the UV, as well as biofilm of the wall of the rearing tanks and the fixed bed biofilter were analysed using 16S rRNA gene amplicon sequencing to elucidate the spatial-temporal microbial dynamics. The results showed that the microbiota composition of water and biofilm varied within and between the production batches, and that the fallowing periods had a substantial effect on the microbial communities. The correlation of the water and biofilm microbiota to fish presence in the system was confirmed by supervised machine learning. Shifts in the composition of the microbiota were identified in conjunction with variations in organic matter loading both during production and fallowing. In addition, variables like oxygen saturation, biomass, and feed type, showed good correlation with variations in the water microbiota composition. Although microbiota changed at fallowing, the microbiota returned to similar compositions during the production phases and was especially evident for the water microbiota. This indicates that the development of microbiota composition is strongly dictated by the similar selection pressure in the system. Nitrifying communities were dominated by Nitrospira, and the third most abundant Nitrospira OTUs were related to the comammox Nitrospira nitrificans. The microbial communities in the biofilter biofilm and water were significantly different but shared abundant taxa and followed the same temporal microbial dynamics and indicates an interaction between the biofilter biofilm and the suspended bacteria. CFU analysis showed that the fraction of rapid-growing bacteria was significantly higher in the rearing water than in the water sump upstream the UV disinfection, indicating that disinfection upstream the rearing tanks allowed for growth of opportunistic bacteria. A community with considerable potential for opportunistic regrowth can have consequences for the microbial water quality and the resistance against pathogen invasion The absence of an in-line disinfection step or placing the disinfection unit upstream the biofilter might provide better microbial water quality and a more resilient system against pathogen proliferation.
•Monitoring of microbial communities in a commercial RAS producing Atlantic salmon•The microbial communities of water and biofilm underwent large changes over time•Microbial communities in biofilm and water were different, but shared many taxa•Nitrospira OTUs were related to the comammox Nitrospira nitrificans
Abstract
Disclosure: Å.B. Sævik: None. G. Ueland: None. A. Åkerman: None. P. Methlie: None. M. Quinkler: None. A. Jørgensen: None. C. Höybye: None. A.W. Debowska: None. B. Nedrebø: None. A. Dahle: ...None. S. Carlsen: None. A.E. Tomkowicz: None. S.T. Sollid: None. I. Nermoen: None. K. Grønning: None. P.M. Dahlqvist: None. G. Grimnes: None. J. Skov: None. T. Finnes: None. S.F. Valland: None. S.E. Holte: None. J. Wahlberg: None. O. Kämpe: None. S. Bensing: None. E.S. Husebye: None. M. Øksnes: None.
Background: Population-based studies have shown a wider use of cardiovascular medications in AAD and an increased risk of ischemic heart disease, most pronounced in women. These data suggest that a subgroup of patients may be especially vulnerable, emphasizing the need for clinical tools to evaluate cardiovascular risk at an individual level in AAD. Methods: We first mapped 177 cardiovascular and inflammatory biomarkers in patients with AAD compared with healthy controls overall and stratified for sex (false discovery rate, FDR 5%). Second, we explored biomarker associations to the frequency of adrenal crises and quality of life (P<0.050), and any impact of very high ACTH exposure on biomarker profiles by change in biomarker profiles in patients without residual adrenocortical function (RAF) following injection of ACTH (FDR 5%). Results: Nineteen (11%) biomarkers significantly differed between patients with AAD and controls after correction for multiple testing, of which all but one (ST1A1) were higher in AAD. The greatest difference in biomarker value was noted for FGF21 (difference 0.80 NPX, P = 0.004). When stratified for sex, seven of the 19 biomarkers were significantly higher in female patients compared to controls (IL6, MCP1, GAL9, SPON2, DR4, RAGE, TNFRSF9 + PGF), but no significant differences were found between male patients and controls. Levels of RAGE correlated with the frequency of adrenal crisis (r = 0.415, P = 0.006) and AddiQoL-30 scores (r = -0.347, P = 0.028). PD-L2 and leptin significantly declined 60 minutes after injection of ACTH in AAD without RAF (-0.15 NPX, P = 0.0001 and -0.25 NPX, P = 0.0003, respectively). Conclusion: We demonstrate marked differences in cardiovascular and inflammatory biomarker profiles in patients with AAD compared with controls, particularly in women. RAGE might be a marker of disease severity in AAD, associated with the frequency of adrenal crises and reduced quality of life. Very high ACTH levels reduce PD-L2 and leptin in a glucocorticoid-independent manner, although the overall effect on biomarker profiles seems small.
Presentation: Saturday, June 17, 2023
The aim of this study was to develop and evaluate the Psychiatric Out-Patient Experiences Questionnaire (POPEQ). The instrument was developed following a literature review, patient interviews and ...pre-testing of questionnaire items. The POPEQ was administered as part of a postal survey of 15,422 adult outpatients attending Norwegian clinics; 6677 (43.3%) patients responded to the questionnaire. Items had low levels of missing data. Factor analysis showed that 11 widely applicable items contribute to a measure of overall experiences. Sub-dimensions include clinician interaction (six items) information (two items) and outcomes (three items). Item-total correlations ranged from 0.5 to 0.8. Cronbach's alpha and test-retest reliability estimates exceeded the criterion of 0.7; the majority were over 0.8 and total scores over 0.9. Construct validity was supported by the results of 128 tests. The POPEQ includes important aspects of patient experience for psychiatric outpatients and has excellent evidence for reliability and construct validity. The instrument is recommended for the measurement of psychiatric outpatient experiences.
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