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Behrens Jane W. Ryberg Marie P. Einberg Heli Eschbaum Redik Florin Ann-Britt Grygiel Wlodzimierz Herrmann Jens Peter Huwer Bastian Hssy Karin Knospina Elina Nomaa Kristiina Oesterwind Daniel Polte Patrick Smoliski Szymon Ustups Didzis van Deurs Mikael Ojaveer Henn 《Biological invasions》2022,24(2):527-541
Biological Invasions - Native to the Ponto-Caspian region, the benthic round goby (Neogobius melanostomus) has invaded several European inland waterbodies as well as the North American Great Lakes... 相似文献
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Forest patches with high biological value are protected as woodland key habitats (WKH), which are identified by the presence
of forest structures and indicator species. However, management for conservation needs to consider also managed forests as
habitats for species. In this respect, there is a need to set quantitative targets for species and structures at different
landscape scales. Due to non-intensive methods of forest management used prior to 1940 in Latvia, it might be expected that
large areas of forest have developed structures that can support many species characteristic of natural forests. The aim of
the study was to create a model that best described the richness of bryophyte species that are characteristic of natural forests,
using forest structures as explanatory factors. The structures and bryophyte communities on living trees and coarse woody
debris (CWD) were described in plots along transects blindly placed in areas dominated by State forests under commercial management.
Explanatory variables related to tree species composition and tree size explained 54% of the variation in WKH indicator species
richness on living trees. The best explanatory factors were maximum diameter of deciduous tree species and CWD. Low richness
of total bryophyte and indicator species was found on dead wood, and the amount of variation in bryophyte species richness
on CWD explained by explanatory variables was low. The study indicates the importance of deciduous tree substrate in managed
forests in maintaining the spatial continuity of epiphytic species diversity. However, the forests in the managed forest landscape
did not support high diversity of epixylic species, even in the WKHs, due to low diversity of suitable dead wood substrate. 相似文献
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For a long time, radial growth of pedunculate oak (Quercus robur) in relation to environmental factors has been studied in Central Europe. However, there is insufficient information on oak growth in the Baltic region. Climate–growth interactions have been mostly investigated by correlation/response analysis between ring width and climatic factors. Other wood anatomical proxies, and also pointer year analysis, which focuses on weather extremes, can be sources of additional information. Wood samples were taken from 40 sites across Latvia. Tree-ring width (TRW) and mean area of earlywood vessels (EVA) were measured. To assess differences in wood formation among sites, a PCA was performed based on pointer year series of TRW and EVA per site. The relation with climate was assessed by Pearson's correlation. Patterns of wood formation differed along west/east gradient, so that two regions (western and eastern) of Latvia were distinguished. Pointer year values were higher for TRW than for EVA and higher in the eastern than in the western region. However, the pointer year values were moderate, suggesting that there was no strict limiting factor for their formation. Pointer years of EVA were strongly related with temperature during the dormant period in both regions; June precipitation had a significant effect in the eastern region. Pointer years of TRW were correlated with spring and summer temperature in the western region and with February temperature in the eastern region; precipitation in autumn showed a negative effect. These differences can be explained by a gradient from maritime to continental climate, leading to shifts in the growth limiting factors. Extremely cold winters resulted in most of the negative pointer years of TRW and EVA. 相似文献
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Sex‐specific compensatory growth in the larvae of the greater wax moth Galleria mellonella 下载免费PDF全文
S. Kecko A. Mihailova K. Kangassalo D. Elferts T. Krama R. Krams S. Luoto M. J. Rantala I. A. Krams 《Journal of evolutionary biology》2017,30(10):1910-1918
Deficiency of food resources in ontogeny is known to prolong an organism's developmental time and affect body size in adulthood. Yet life‐history traits are plastic: an organism can increase its growth rate to compensate for a period of slow growth, a phenomenon known as ‘compensatory growth’. We tested whether larvae of the greater wax moth Galleria mellonella can accelerate their growth after a fast of 12, 24 or 72 h. We found that a subgroup of female larvae showed compensatory growth when starved for 12 h. Food deficiency lasting more than 12 h resulted in longer development and lower mass gain. Strength of encapsulation reactions against a foreign body inserted in haemocoel was the weakest in females that showed compensatory growth, whereas the strongest encapsulation was recorded in the males and females that fasted for 24 and 72 h. More specifically, we found sex‐biased immune reactions so that females had stronger encapsulation rates than males in one group that fasted for 72 h. Overall, rapidly growing females had a short larval development period and the shortest adult lifespan. These results suggest that highly dynamic trade‐offs between the environment, life‐history traits and sex lead to plasticity in developmental strategies/growth rates in the greater wax moth. 相似文献
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Food quality affects the expression of antimicrobial peptide genes upon simulated parasite attack in the larvae of greater wax moth 下载免费PDF全文
Indrikis Krams Sanita Kecko Inna Inashkina Giedrius Trakimas Ronalds Krams Didzis Elferts Jolanta Vrublevska Priit Jõers Markus J. Rantala Severi Luoto Jorge Contreras‐Garduño Līga Jankevica Laila Meija Tatjana Krama 《Entomologia Experimentalis et Applicata》2017,165(2-3):129-137
Predator‐prey interactions are an important evolutionary force affecting the immunity of the prey. Parasitoids and mites pierce the cuticle of their prey, which respond by activating their immune system against predatory attacks. Immunity is a costly function for the organism, as it often competes with other life‐history traits for limited nutrients. We tested whether the expression of antimicrobial peptides (AMP) of the larvae of the greater wax moth Galleria mellonella (L.) (Lepidoptera: Pyralidae) changes as a consequence of insertion of a nylon monofilament, which acts like a synthetic parasite. The treatment was done for larvae grown on a high‐quality vs. a low‐quality diet. The expression of Gloverin and 6‐tox were upregulated in response to the insertion of the nylon monofilament. The expression of 6‐tox, Cecropin‐D, and Gallerimycin were significantly higher in the ‘low‐quality diet’ group than in the ‘high‐quality diet’ group. As food quality seems to affect AMP gene expression in G. mellonella larvae, it should always be controlled for in studies on bacterial and fungal infections in G. mellonella. 相似文献
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Indrikis A. Krams Katariina Rumvolt Lauri Saks Ronalds Krams Didzis Elferts Jolanta Vrublevska Markus J. Rantala Sanita Kecko Dina Cīrule Severi Luoto Tatjana Krama 《Ecological Research》2017,32(4):559-566
Vertebrates differ in their ability to mount an adaptive immune response to novel antigens. Bioenergetic resources available to an organism are finite; investment in reproduction compromises immune function and may therefore affect critical life history trade-offs. We tested whether reproduction impairs the ability to produce an antibody response against a novel antigen in roach (Rutilus rutilus). The antigen approach has rarely been used in fish studies, and the ability to produce an antibody response during reproductive season has never been tested in cyprinid fish before. The fish in an experimental group were injected with a Brucella abortus (BA) antigen, while the fish in a control group were injected with an isotonic saline solution. Blood samples were extracted from all the fish to obtain the total number and proportion of blood cells such as lymphocytes, neutrophils and antioxidant glutathione. The groups were tested during the spawning season and one week after it had ended. The roach were unable to mount an immune response during spawning but produced a robust response after it. We conclude that reproduction is costly in roach, as indicated by the increased concentration of neutrophils in fish injected with BA during spawning, as well as the negative associations between neutrophil counts and glutathione levels. This study demonstrates the potential of BA antigen as a research tool in experimental research on fish ecological immunology. 相似文献
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