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71.
72.
《Journal of bryology》2013,35(2):154-157
AbstractWe revised both the holotype and an isotype of Riccia teneriffae S.W.Arnell 1962 and additionally revised our own collections of Riccia cavernosa Hoffm. 1795 from the Canary Islands. Since the types of R. teneriffae represent R. cavernosa, and the latter name precedes the former, R. teneriffae should be treated as a synonym of R. cavernosa. In the Canary Islands, R. cavernosa appears to be rare. It has been found on La Gomera, Gran Canaria, Lanzarote, and Tenerife. We report it as new to Fuerteventura. R. cavernosa inhabits ephemeral, thin layers of mud. Very rarely it occurs on basaltic pyroclasts. SEM images of spores are presented. The local distribution is mapped. 相似文献
73.
Vadim Bakalin Vladimir Fedosov Olga Pisarenko Eugene Borovichev 《Journal of bryology》2013,35(3):249-262
Introduction. The Kuril Islands Chain demarcates the boundary between the circumpolar and East Asian floras in the amphi-Pacific and is a trans-Oceanic migration route from warm-temperate insular East Asia to north-east Asia and Beringia. This paper reviews the flora of the northern part of Iturup Island in regards to its bryogeography and taxonomic diversity, as well as its relative position among other bryophyte floras of north-east and East Asia.Methods. The paper uses morphological methods to identify the species composition and detrended correspondence analysis to identify the position of the northern Iturup Island in the system of local floras of the eastern, extra-tropical, Pacific.Key results. The flora is closely related to the bryophyte floras of the southern Kurils and Hokkaido Island, but has been found to be distinctly distant from the ‘true’ cool-temperate East Asian floras, as well as from the boreal and hemiarctic floras of north-east Asia. Instead, the floras of the south Kurils and northern Hokkaido Island belong to a peculiar intermediate phytogeographic province that cannot be unambiguously placed in either the East Asian or circumboreal floristic regions. The hemiboreal character of the bryophyte flora of northern Iturup Island is in contrast to the general appearance of many of the dominant vegetation communities on the island, which are more characteristic of the hemiarctic.Conclusion. There is no robust evidence to refer the bryophyte flora of northern Iturup either to the circumboreal or East Asian Floristic Region, the flora belongs to a unique intermediate province between the two regions. 相似文献
74.
Heriberto López Hermans G. Contreras-Díaz Pedro Oromí Carlos Juan 《Conservation Genetics》2007,8(3):587-598
Mitochondrial DNA cytochrome oxidase subunit I and nuclear ITS2 sequences were surveyed from Canary Islands threatened species
of the genera Purpuraria and Acrostira (Orthoptera: Pamphagidae). Phylogenetic and population analyses show that the two previously recognized Purpuraria erna subspecies are not valid as conservation units, and that there is a new unrecognized species of Purpuraria, coincident with recently discovered morphological variation within the genus. In addition, mitochondrial introgression seems
to occur between the two Purpuraria species in southwest Lanzarote. Species-delimitation based on the morphological taxonomy of Acrostira, which recognizes four single-island endemics, is only partially supported by the genetic data. It shows that currently admitted
species from the central and western islands of Tenerife, La Gomera and La Palma are closely related, with evidence of recent
gene flow between the Tenerife and La Gomera populations. MtDNA variation also showed that A. euphorbiae, currently considered as the most critically endangered grasshopper species in the Canaries, has lower population diversity
than its close relatives. 相似文献
75.
Russell H. Messing Michelle N. Tremblay Edward B. Mondor Robert G. Foottit Keith S. Pike 《Biological invasions》2007,9(5):601-607
Invasive species have had devastating impacts on the fauna and flora of the Hawaiian Islands. While the negative effects of
some invasive species are obvious, other species are less visible, though no less important. Aphids (Homoptera: Aphididae)
are not native to Hawai’i but have thoroughly invaded the Island chain, largely as a result of anthropogenic influences. As
aphids cause both direct plant feeding damage and transmit numerous pathogenic viruses, it is important to document aphid
distributions and ranges throughout the archipelago. On the basis of an extensive survey of aphid diversity on the five largest
Hawaiian Islands (Hawai’i, Kaua’i, O’ahu, Maui, and Moloka’i), we provide the first evidence that invasive aphids feed not
just on agricultural crops, but also on native Hawaiian plants. To date, aphids have been observed feeding and reproducing
on 64 native Hawaiian plants (16 indigenous species and 48 endemic species) in 32 families. As the majority of these plants
are endangered, invasive aphids may have profound impacts on the island flora. To help protect unique island ecosystems, we
propose that border vigilance be enhanced to prevent the incursion of new aphids, and that biological control efforts be renewed
to mitigate the impact of existing species. 相似文献
76.
A new species of Neopetitia San Martín, 2003 is described from intertidal and shallow subtidal soft-bottom stations on the eastern and western coast of Tenerife, Canary
Islands. The new species is characterized by the presence in males of a modified acicular chaeta in chaetiger 11. A discussion
of known species of the genus is presented. 相似文献
77.
采用高通量测序-分子鉴定分级技术于2019年对长山群岛全海域真核微藻粒级结构进行了研究。结果发现,春季以中(47%)、小粒级(41%)为主,夏季以小(39%)、大粒级(38%)为主,秋季以大粒级(60%)为主,春、夏、秋季小、中、大粒级微藻比例为42:47:11、39:23:38、22:18:60。小粒级微藻优势种为细小微胞藻(Micromonas pusilla)、融合微胞藻(Micromonas commoda)和金牛微球藻(Ostreococcus tauri),中粒级微藻优势种为剧毒卡尔藻(Karlodinium veneficum)、大粒级微藻优势种为柔弱几内亚藻(Guinardia delicatula)、平野亚历山大藻(Alexandrium hiranoi)、多纹膝沟藻(Gonyaulax polygramma),综合整个真核微藻群落,春季由中粒径的剧毒卡尔藻占据优势(23.9%),夏季由大粒径的平野亚历山大藻占据优势(29.4%),秋季由大粒径的多纹膝沟藻占据优势(66.8%),有毒甲藻在该海域中占有绝对优势,贝毒累积风险较高,小粒径微藻中金牛微球藻和抑食金球藻曾在渤海引发褐潮,潜在威胁该海域贝类养殖业。虾夷扇贝对小粒级和大粒级微藻的选择性较低,对中粒级微藻的选择性较高,尤其对水体中优势种剧毒卡尔藻一直表现出主动选择。光学需氧量、无机氮、溶解氧、石油类及部分重金属Cd、As、Hg影响着整个长山群岛海域真核微藻粒级结构时空演变。 相似文献
78.
In the past years, efforts have been made to include connectivity metrics in conservation planning in order to promote and enhance well-connected systems of protected areas. Connectivity is particularly important for species that rely on more than one realm during their daily or life cycle (multi-realm species). However, conservation plans for the protection of multi-realm species usually involve a single realm, excluding other realms from the prioritization process. Here, we demonstrate an example of cross-realm conservation planning application for the island of Cyprus by taking into account the terrestrial and marine realms and their interface (i.e. coast). Operating within a data-poor context, we use functional connectivity metrics to identify priority areas for the conservation of six multi-realm species, by setting conservation targets simultaneously for the terrestrial and marine realms. MARXAN decision-support tool was used for the identification of the priority areas.Four scenarios were developed to evaluate the impacts of including connectivity in the prioritization process and the effectiveness of the existing coastal/marine protected areas in the achievement of the conservation targets set for the species. All scenarios considered land and sea anthropogenic uses as surrogate costs to influence the prioritization process.Our findings show an increase in the area of the reserve network and, therefore, the cost, when connectivity is included, whilst reducing the total boundary length. Furthermore, the current reserve network fails to achieve conservation targets, particularly for the marine part, which has a substantially smaller protection coverage than the terrestrial part.We conclude that focus should be given in the expansion of the current coastal/marine reserve network following a cross-realm conservation approach. This approach is not only relevant for the conservation of multi-realm species, but also for islandscapes, in particular, where the interdependence between the hinterland and the coast is larger and therefore the magnitude of the impacts generated in one realm and affects the other. 相似文献
79.
Tyler J. Clark Anne‐Sophie Bonnet‐Lebrun Letizia Campioni Paulo Catry Ewan Wakefield 《Ibis》2019,161(1):192-197
The Sooty Shearwater Ardenna grisea, an abundant but declining petrel, is one of many seabird species that construct breeding burrows, presumably because these confer protection from predators and the elements. Little is known about the causes of variation in Sooty Shearwater burrow architecture, which can differ markedly both within and between breeding sites. We hypothesize that burrow architecture varies in response to habitat type and competition for space. To address these hypotheses, we recorded Sooty Shearwater burrow dimensions on Kidney Island, the largest Sooty Shearwater colony in the Falkland Islands, South Atlantic, and modelled these as functions of burrow density (a proxy for competition) and habitat indices. Our models suggest that Sooty Shearwaters burrow further underground in response to competition for breeding space, and that soil underlying dense tussac grass Poa flabellata is more easily excavated than other substrates, indicating how vegetation restoration could aid the conservation of this species. 相似文献
80.
Ninety-six juvenile specimens (37–54 mm standard length; LS) of the rarely collected Upward-Mouth Spikefish Atrophacanthus japonicus (Triacanthodidae) were obtained from the stomachs of three Yellowfin Tuna Thunnus albacares collected off Guam in the Mariana Islands in the central Pacific Ocean. These specimens extend the range of A. japonicus eastward into Oceania. We review the systematic characters of the monotypic genus Atrophacanthus and present colour photographs of freshly collected specimens. The diet of the juvenile specimens of A. japonicus consisted of thecosome pteropods and foraminiferans. We present a range map of A. japonicus based on all known specimens and show that specimen size is related to whether specimens were collected in the pelagic zone or on the bottom. Our results support that, compared to all other Triacanthodidae, A. japonicus has an unusually extended pelagic larval and juvenile period, up to 54 mm LS, before settling to the bottom as adults. Lastly, we provide a multilocus phylogeny addressing the phylogenetic placement of Atrophacanthus based on eight of 11 triacanthodid genera and six genetic markers. Our results reveal that Atrophacanthus is the sister group of Macrorhamphosodes and they provide new insights about the evolutionary history of the family. 相似文献