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991.
992.
Fernandez M. Pilar Ernst Kacey C. Bron Gebbiena M. Berry Kevin Diuk-Wasser Maria A. Hayden Mary H. 《EcoHealth》2022,19(2):154-158
EcoHealth - Shifts in activity patterns during the COVID-19 pandemic might have impacted the benefits of outdoor activities for mental health. By leveraging an existing mobile application, we... 相似文献
993.
994.
Emma Morrissey-McCaffrey Samuel Shephard Fiona L. Kelly Mary Kelly-Quinn 《Journal of fish biology》2019,94(1):5-16
This study finds that non-native species and warming temperatures have significant negative effects on Arctic char Salvelinus alpinus abundance in Irish lakes. Eutrophication was not important at the range of total phosphorus tested (0.005–0.023 mg l−1). Model results predict that S. alpinus occur across the temperature range sampled (8.2–19.7°C) when non-natives are absent, but S. alpinus catch is predicted to be close to zero irrespective of temperature when non-native catch is high. This result indicates that to persist, S. alpinus may require a habitat where non-natives are at low abundance or absent. Salvelinus alpinus segregated from other species along the thermal axis, inhabiting significantly colder water and actively avoided non-native species, which appeared to limit their distribution. The thermal niche realized by S. alpinus in non-native dominated lakes was thus compressed relative to native dominated lakes and S. alpinus population density was significantly lower. These findings were consistent even when the only non-native present was Perca fluviatilis. Temperature appeared to limit the distribution of non-native species, such that the presence of deep thermal refugia is currently facilitating S. alpinus co-existence with non-natives in associated lakes. Diet analysis identified P. fluviatilis as potential predators and competitors. This study provides strong evidence that non-native species are a key driver of low S. alpinus abundance in Irish lakes. Temperature increases associated with climate change are identified as a secondary concern, as they could erode S. alpinus' thermal niche and lead to their extirpation. The lower thermal buffering capacity of shallow lakes identifies these as higher risk systems. Salvelinus alpinus conservation in Ireland should focus on preventing future illegal non-native species introductions because unlike other stressors (e.g., eutrophication etc.), species introductions are rarely reversible. 相似文献
995.
Jeffery R. Hughey Christine A. Maggs Frdric Mineur Charlie Jarvis Kathy Ann Miller Soha Hamdy Shabaka Paul W. Gabrielson 《Journal of phycology》2019,55(3):503-508
Current usage of the name Ulva lactuca, the generitype of Ulva, remains uncertain. Genetic analyses were performed on the U. lactuca Linnaean holotype, the U. fasciata epitype, the U. fenestrata holotype, the U. lobata lectotype, and the U. stipitata lectotype. The U. lactuca holotype is nearly identical in rbcL sequence to the epitype of U. fasciata, a warm temperate to tropical species, rather than the cold temperate species to which the name U. lactuca has generally been applied. We hypothesize that the holotype specimen of U. lactuca came from the Indo‐Pacific rather than northern Europe. Our analyses indicate that U. fasciata and U. lobata are heterotypic synonyms of U. lactuca. Ulva fenestrata is the earliest name for northern hemisphere, cold temperate Atlantic and Pacific species, with U. stipitata a junior synonym. DNA sequencing of type specimens provides an unequivocal method for applying names to Ulva species. 相似文献
996.
997.
Ga Hun Boo Ying‐Xiong Qiu Jung Yeon Kim Put O. Ang Samuel Bosch Olivier De Clerck Peimin He Atsushi Higa Bangqin Huang Kazuhiro Kogame Shao‐Lun Liu Tu van Nguyen Shoichiro Suda Ryuta Terada Kathy Ann Miller Sung Min Boo 《Journal of phycology》2019,55(6):1319-1334
The evolutionary and population demographic history of marine red algae in East Asia is poorly understood. Here, we reconstructed the phylogeographies of two upper intertidal species endemic to East Asia, Gelidiophycus divaricatus and G. freshwateri. Phylogenetic and phylogeographic inferences of 393 mitochondrial cox1, 128 plastid rbcL, and 342 nuclear ITS2 sequences were complemented with ecological niche models. Gelidiophycus divaricatus, a southern species adapted to warm water, is characterized by a high genetic diversity and a strong geographical population structure, characteristic of stable population sizes and sudden reduction to recent expansion. In contrast, G. freshwateri, a northern species adapted to cold temperate conditions, is genetically relatively homogeneous with a shallow population structure resulting from steady population growth and recent equilibrium. The overlap zone of the two species roughly matches summer and winter isotherms, indicating that surface seawater temperature is a key feature influencing species range. Unidirectional genetic introgression was detected at two sites on Jeju Island where G. divaricatus was rare while G. freshwateri was common, suggesting the occurrence of asymmetric natural hybrids, a rarely reported event for rhodophytes. Our results illustrate that Quaternary climate oscillations have left strong imprints on the current day genetic structure and highlight the importance of seawater temperature and sea level change in driving speciation in upper intertidal seaweed species. 相似文献
998.
The larval pre-competency period and competency window are important in delimiting the potential dispersal distance for pelagic larvae of sessile marine fauna. Here, we provide evidence for morphological changes in the late planulae of Lophelia pertusa that have implications for their dispersal potential. Three weeks after spawning, the planulae gain functional cnidocysts, indicating that they are competent to settle at this time. Cnidae have been shown to be used for primary anchoring during settling, and before this time point, the larvae most probably do not have the ability to attach to a substrate in high flow conditions. The appearance of functional cnidae coincides with larvae gaining a flexible mouth that can be opened to the full width of the larva. The larval isorhizas differ the most from the adult polyps isorhizas, while the p- and b-mastigophores bear more resemblance to the adult homologues of similar size. The external and internal morphology of late planulae is further described with demonstration of long apical cilia and its effect on swimming agility, morphological changes of the ciliated cells in the larval mouth region and an internal nerve plexus. This study also indicates that L. pertusa planulae seek out cryptic spaces for settling. 相似文献
999.
1000.
Aldi T. Kraja Chunyu Liu Jessica L. Fetterman Mariaelisa Graff Christian Theil Have Charles Gu Lisa R. Yanek Mary F. Feitosa Dan E. Arking Daniel I. Chasman Kristin Young Symen Ligthart W. David Hill Stefan Weiss Jian’an Luan Franco Giulianini Ruifang Li-Gao Fernando P. Hartwig Kari E. North 《American journal of human genetics》2019,104(1):112-138