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1.
PLoS One ; 17(9): e0273354, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36174081

RESUMO

Tourism and nature-based recreation has changed dramatically during the COVID-19 pandemic. Travel restrictions caused sharp declines in visitation numbers, particularly in remote areas, such as northern Norway. In addition, the pandemic may have altered human-nature relationships by changing visitor behaviour and preferences. We studied visitor numbers and behaviour in northern Norway, based on user-generated data, in the form of photographic material that was uploaded to the popular online platform Flickr. A total of 195.200 photographs, taken by 5.247 photographers were subjected to Google's "Cloud Vision" automatic content analysis algorithm. The resulting collection of labels that were assigned to each photograph was analysed in structural topic models, using photography date (relative to the start of the pandemic measures in Norway) and reported or estimated photographers' nationality as explanatory variables. Our results show that nature-based recreation relating to "mountains" and "winter" became more prevalent during the pandemic, amongst both domestic and international photographers. Shifts in preferences due to the pandemic outbreak strongly depended on nationality, with domestic visitors demonstrating a wide interest in topics while international visitors maintained their preference for nature-based experiences. Among those activities that suffered the most from decline in international tourism was northern lights and cruises as indicated by the topic models. On the other hand, images depicting mountains and flora and fauna increased their prevalence during the pandemic. Domestic visitors, on the other hand, spent more time in urban settings as a result of restrictions, which results in a higher prevalence of non-nature related images. Our results underscore the need to consider the dynamic nature of human-nature relationships. The contrast in flexibility to adapt to changing conditions and travel restrictions should be incorporated in collaborative efforts of municipalities and tour operators to develop sustainable local nature-based tourism products, particularly in remote areas.


Assuntos
COVID-19 , Turismo , COVID-19/epidemiologia , Características Humanas , Humanos , Pandemias , Viagem
2.
Ecol Evol ; 11(15): 10483-10488, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34367590

RESUMO

Stable isotopes analysis (SIA) of carbon and nitrogen provides valuable information about trophic interactions and animal feeding habits.We used near-infrared reflectance spectroscopy (NIRS) and support vector machines (SVM) to develop a model for screening isotopic ratios of carbon and nitrogen (δ 13C and δ 15N) in samples from living animals. We applied this method on dried blood samples from birds previously analyzed for δ 13C and δ 15N to test whether NIRS can be applied to accurately estimate isotopic ratios.Our results show a prediction accuracy of NIRS (R 2 > 0.65, RMSEP < 0.28) for both δ 13C and δ 15N, representing a 12% of the measurement range in this study.Our study suggests that NIRS can provide a time- and cost-efficient method to evaluate stable isotope ratios of carbon and nitrogen when substantial differences in δ 13C or δ 15N are expected, such as when discriminating among different trophic levels in diet.

3.
Front Vet Sci ; 8: 707787, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34712719

RESUMO

Background: Previous serological screenings have indicated that Eurasian semi-domesticated tundra reindeer (Rangifer tarandus tarandus) in Finnmark, Northern Norway, are exposed to alphaherpesvirus, gammaherpesvirus and pestivirus. Alphaherpesvirus (i.e., Cervid herpesvirus 2; CvHV2) has been identified as the transmissible component of infectious keratoconjunctivitis (IKC). Limited knowledge exists on the presence and prevalence of virus infections in other herding regions in Norway, which are hosting ~67,000 semi-domesticated reindeer and have contact with other species and populations of wildlife and livestock than those present in Finnmark. Methods: Blood samples (n = 618) were obtained over five winter seasons (2013-2018), from eight different herds representing summer pasture districts in Tana, Lakselv, Tromsø, Lødingen, Hattfjelldal, Fosen, Røros, and Filefjell, distributed from North to South of the reindeer herding regions in Norway. Blood samples were investigated for specific antibodies against five viral pathogen groups, alphaherpesvirus, gammaherpesvirus (viruses in the malignant catarrhal fever group; MCFV), pestivirus, bluetongue virus (BTV), and Schmallenberg virus (SBV), by using commercial multispecies serological tests (ELISA). In addition, swab samples obtained from the nasal mucosal membrane from 486 reindeer were investigated by PCR for parapoxvirus-specific DNA. Results: Antibodies against aphaherpesvirus and MCFV were found in all eight herds, with a total prevalence of 42% (range 21-62%) and 11% (range 2-15%), respectively. Anti-Pestivirus antibodies were detected in five of eight herds, with a total prevalence of 19% (range 0-52%), with two of the herds having a particularly high seroprevalence. Antibodies against BTV or SBV were not detected in any of the animals. Parapoxvirus-specific DNA was detected in two animals representing two different herds in Finnmark. Conclusions: This study confirmed that alphaherpesvirus and MCFV are enzootic throughout the geographical reindeer herding regions in Norway, and that pestivirus is present in most of the herds, with varying seroprevalence. No exposure to BTV and SBV was evident. This study also indicated that semi-domesticated reindeer in Finnmark are exposed to parapoxvirus without disease outbreaks being reported from this region.

4.
Front Vet Sci ; 6: 461, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31921918

RESUMO

Captive reindeer in German zoos and wildlife parks live outside their natural geographic range and are exposed to a variety of viral, bacterial and protozoan pathogens, some host-specific and some which they are not exposed to in their native habitat. Reindeer blood samples and ticks collected in 2013 from 123 reindeer at 16 different zoological facilities were available from a previous study. The aims of this study were to assess the serological status of these animals with regards to various microorganisms as well as to test ticks (Ixodes ricinus) and blood samples for the presence of Anaplasma spp. DNA in order to evaluate the exposure of captive reindeer in Germany to a variety of pathogens. A total of 119 or 118 serum samples were screened (ELISA) and antibodies were detected (seropositive/tested, prevalence, confidence interval) against alphaherpesvirus (24/119, 20.3%, CI: 13.9-28.3), bluetongue virus (BTV; 4/119, 3.4%, CI: 1.0-8.7), malignant catarrhal fever related gammaherpesvirus (MCFV-related gammaherpesvirus; 7/119, 5.9%, CI: 2.7-11.9), pestivirus (5/118, 4.2%, CI: 1.6-9.8), Schmallenberg virus (SBV; 70/118, 59.3%, CI: 50.3-67.8), smooth Brucella spp. (1/118; 0.9%, CI: 0-5.1), Neospora caninum (5/118, 4.2%, CI: 1.6-9.8), and Toxoplasma gondii (62/119, 52.1%, CI: 43.2-60.9). These results suggested the exposure of reindeer to all tested pathogens. Moreover, real-time PCR for Anaplasma phagocytophilum targeting the partial msp2 gene was performed on DNA extracted from whole blood samples from reindeer (n = 123) and from ticks (n = 49) collected from 22 reindeer in seven different facilities. In addition to the real-time PCR, a semi-nested PCR for the partial groEL gene, and a nested PCR targeting the partial 16S rRNA gene were performed. DNA of A. phagocytophilum was detected in 17 reindeer (13.8%) and 15 ticks (30.6%). Three of the five reindeer with ticks having A. phagocytophilum DNA also had such DNA in blood. These results indicate that captive reindeer can be exposed to several ruminant pathogens that they hitherto had no known exposure to through their natural geographical distribution and habitats as shown for Culicoides-borne BTV and SBV. Further, captive reindeer may serve as reservoir hosts for pathogens circulating in local domestic, captive, and wild ruminant species and populations and arthropod vectors.

5.
Front Plant Sci ; 5: 496, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25309567

RESUMO

Silicon (Si) is one of the most common elements in the earth bedrock, and its continental cycle is strongly biologically controlled. Yet, research on the biogeochemical cycle of Si in ecosystems is hampered by the time and cost associated with the currently used chemical analysis methods. Here, we assessed the suitability of Near Infrared Reflectance Spectroscopy (NIRS) for measuring Si content in plant tissues. NIR spectra depend on the characteristics of the present bonds between H and N, C and O, which can be calibrated against concentrations of various compounds. Because Si in plants always occurs as hydrated condensates of orthosilicic acid (Si(OH)4), linked to organic biomolecules, we hypothesized that NIRS is suitable for measuring Si content in plants across a range of plant species. We based our testing on 442 samples of 29 plant species belonging to a range of growth forms. We calibrated the NIRS method against a well-established plant Si analysis method by using partial least-squares regression. Si concentrations ranged from detection limit (0.24 ppmSi) to 7.8% Si on dry weight and were well predicted by NIRS. The model fit with validation data was good across all plant species (n = 141, R (2) = 0.90, RMSEP = 0.24), but improved when only graminoids were modeled (n = 66, R (2) = 0.95, RMSEP = 0.10). A species specific model for the grass Deschampsia cespitosa showed even slightly better results than the model for all graminoids (n = 16, R (2) = 0.93, RMSEP = 0.015). We show for the first time that NIRS is applicable for determining plant Si concentration across a range of plant species and growth forms, and represents a time- and cost-effective alternative to the chemical Si analysis methods. As NIRS can be applied concurrently to a range of plant organic constituents, it opens up unprecedented research possibilities for studying interrelations between Si and other plant compounds in vegetation, and for addressing the role of Si in ecosystems across a range of Si research domains.

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