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61.
Daniele De Barba Sergio Rossi Annie Deslauriers Hubert Morin 《Trees - Structure and Function》2016,30(1):87-97
Key message
In mature black spruce, bud burst process is anticipated by soil warming, while delayed by foliar applications of nitrogen; however, the effects depend on growth conditions at the site.Abstract
The observation of phenological events can be used as biological indicator of environmental changes, especially from the perspective of climate change. In boreal forests, the onset of the bud burst is a key factor in the length of the growing season. With current climate change, the major factors limiting the growth of boreal trees (i.e., temperature and nitrogen availability) are changing and studies on mature trees are limited. The aim of this study was to investigate the effects of soil warming and increased nitrogen (N) deposition on bud burst of mature black spruce [Picea mariana (Mill.) BSP]. From 2008 onwards, an experimental manipulation of these environmental growth conditions was conducted in two stands (BER and SIM) at different altitudes in the boreal forest of Quebec, Canada. An increase in soil temperature (H treatment) and a canopy application of artificial rain enriched with nitrogen (N treatment) were performed. Observations of bud phenology were made during May–July 2012 and 2013. In BER, H treatment caused an anticipation (estimated as 1–3 days); while N treatment, a delay (estimated as 1–2 days but only in 2012) in bud burst. No treatments effect was significant in SIM. It has been demonstrated that soil temperature and N availability can play an important role in affecting bud burst in black spruce but the effects of these environmental factors on growth are closely linked with site conditions.62.
Amy M. Van Cise Robin W. Baird Charles Scott Baker Salvatore Cerchio Diane Claridge Russell Fielding Brittany Hancock‐Hanser Jacobo Marrero Karen K. Martien Antonio A. Mignucci‐Giannoni Erin M. Oleson Marc Oremus M. Michael Poole Patricia E. Rosel Barbara L. Taylor Phillip A. Morin 《Molecular ecology》2019,28(11):2886-2902
Genomic phylogeography plays an important role in describing evolutionary processes and their geographic, ecological, or cultural drivers. These drivers are often poorly understood in marine environments, which have fewer obvious barriers to mixing than terrestrial environments. Taxonomic uncertainty of some taxa (e.g., cetaceans), due to the difficulty in obtaining morphological data, can hamper our understanding of these processes. One such taxon, the short‐finned pilot whale, is recognized as a single global species but includes at least two distinct morphological forms described from stranding and drive hunting in Japan, the “Naisa” and “Shiho” forms. Using samples (n = 735) collected throughout their global range, we examine phylogeographic patterns of divergence by comparing mitogenomes and nuclear SNP loci. Our results suggest three types within the species: an Atlantic Ocean type, a western/central Pacific and Indian Ocean (Naisa) type, and an eastern Pacific Ocean and northern Japan (Shiho) type. mtDNA control region differentiation indicates these three types form two subspecies, separated by the East Pacific Barrier: Shiho short‐finned pilot whale, in the eastern Pacific Ocean and northern Japan, and Naisa short‐finned pilot whale, throughout the remainder of the species' distribution. Our data further indicate two diverging populations within the Naisa subspecies, in the Atlantic Ocean and western/central Pacific and Indian Oceans, separated by the Benguela Barrier off South Africa. This study reveals a process of divergence and speciation within a globally‐distributed, mobile marine predator, and indicates the importance of the East Pacific Barrier to this evolutionary process. 相似文献
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64.
Julie Neury‐Ormanni Caroline Doose Nabil Majdi Jacky Vedrenne Soizic Morin Sebastian Hss Walter Traunspurger 《Invertebrate Biology》2019,138(4)
The neonicotinoid imidacloprid and the herbicide diuron are long‐lived pesticides commonly detected in European rivers. Both have lethal as well as sublethal effects on aquatic invertebrates dwelling in streambeds. Here, we performed lethality tests of imidacloprid and diuron on seven species of widespread, free‐living nematodes and the model organism Caenorhabditis elegans. Our results indicated that nematodes were relatively tolerant to both pesticides, and only two species (Diploscapter coronatus and Plectus opisthocirculus) showed mortality at high nominal concentrations of imidacloprid (119 mg/L) and diuron (33 mg/L). The changes observed in nematode community structure after imidacloprid and diuron exposure may have been related to trade‐offs between sensitivity to toxicants and changes in competitive abilities of the species. While the former can be tested using single‐species tests, we recommend that the latter be tested in further experiments using multispecies communities. Our results suggest that the presence of these pesticides could favor nematodes over other meiofaunal groups found in freshwater sediments. 相似文献
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66.
Beginning in the early 1990s, the balsam fir sawfly (Neodiprion abietis) became a significant defoliating insect of precommercially thinned balsam fir (Abies balsamea (L.) Mill.) stands in western Newfoundland, Canada. In 1997, a nucleopolyhedrovirus (NeabNPV) was isolated from the balsam
fir sawfly and, as no control measures were then available, NeabNPV was developed for the biological control of balsam fir
sawfly. In order to register NeabNPV for operational use under the Canadian Pest Control Products Act, research was carried
out in a number of areas including NeabNPV field efficacy, non-target organism toxicology, balsam fir sawfly ecology and impact
on balsam fir trees, and NeabNPV genome sequencing and analysis. As part of the field efficacy trials, approximately 22 500
hectares of balsam fir sawfly-infested forest were aerially treated with NeabNPV between 2000 and 2005. NeabNPV was found
to be safe, efficacious, and economical for the suppression of balsam fir sawfly outbreak populations. Conditional registration
for the NeabNPV-based product, Abietiv™, was received from the Pest Management Regulatory Agency (Health Canada) in April
2006. In July 2006, Abietiv was applied by spray airplanes to 15 000 ha of balsam fir sawfly-infested forest in western Newfoundland
in an operational control program.
相似文献
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68.
Delphine Durette‐Morin Kimberley T. A. Davies Hansen D. Johnson Moira W. Brown Hilary Moors‐Murphy Bruce Martin Christopher T. Taggart 《Marine Mammal Science》2019,35(4):1280-1303
North Atlantic right whale monitoring in Roseway Basin, Canada, is primarily based on short‐term (<14 d) visual surveys conducted during August–September. Variability in survey effort has been the biggest limiting factor to studying changes in the population's occurrence and habitat use. Such efforts could be enhanced considerably using passive acoustic monitoring (PAM). We sought to determine if variation in whale presence, relative abundance, demography, and/or behavior (estimated through visual surveys) could be explained by variation in three right whale call types in this habitat. A generalized linear model was fit to 23 d of concurrent PAM and visual monitoring during four summers within the Roseway Basin Right Whale Critical Habitat boundaries. The model revealed significant positive relationships between relative abundance, call counts and presence of surface‐active group behavior. PAM can refine daily right whale presence estimates. While visual observations (n = 23 d) implied a 40% decline in right whale presence during 2014–2015 relative to 2004–2005, PAM data (n = 211 d) showed right whales were present between 71%–85% of survey days throughout all years analyzed. We demonstrate that PAM is a useful tool to extend periods of right whale monitoring, especially in areas where visual monitoring efforts may be limited. 相似文献
69.
Christelle Monteil Caroline Leclere Franoise Dantzer Veronika Elkaz Jean-Paul Fillastre Jean-Paul Morin 《Cell biology international》1993,17(10):953-960
We have assessed the impact of increasing oxygen availability on cellular phenotype expression of rabbit proximal tubule cells in primary culture developed with variable glucose and/or insulin contents. To mitigate hypoxia at the cell/medium interface, cells were shaken for the whole culture duration and their expressed phenotype was compared with those expressed by static cultures. O2 and CO2 tensions were kept constant in the incubator atmosphere. Glycolysis and gluconeogenesis pathways, detoxication system, and mitochondrial, apical and basolateral membrane marker enzyme activities were assessed. This study showed that the induction of glycolysis which appear in primary cultures of proximal tubule cells may be partially prevented by continuously shaking the cultures. This effect was more marked in the presence of glucose, suggesting better substrate oxidation in shaken cultures. 相似文献
70.
H Toutain N Vauclin-Jacques J P Fillastre J P Morin 《Cell biology international reports》1989,13(8):701-710
A pure suspension of proximal tubule cells from the rabbit kidney was isolated by a new procedure, without proteolytic enzyme treatment. Electron microscopic examination revealed that these intact cells had long microvilli. All the marker enzymes located in the proximal tubule were higher in the isolated cells compared with renal cortex. Adenylate cyclase activity of the isolated cells was increased by PTH and NaF stimulations, while other hormones had minor effects. This isolated cell suspension showed a high respiration rate, a linear glucose production and a normal cell ATP level. All these results confirmed the isolation of viable proximal tubular cells with high metabolic capacities from the rabbit kidney. 相似文献