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1.
Invasive vegetation species can lead to major changes in the geomorphology of coastal systems. Within temperate estuaries in the southern hemisphere, especially Australia and New Zealand, the cordgrass Spartina spp. has become established. These species are highly invasive, and their prolific growth leads to the development of supratidal environments in formerly intertidal and subtidal environments. Here, we quantified the impact of Spartina invasion on the geomorphology and sequestration capacity of carbon in the sediments of Anderson Inlet, Victoria, Australia. Spartina was first introduced to the area in the 1930s to aid in land reclamation and control coastal erosion associated with coastal development. We found that Spartina now dominates the intertidal areas of the Inlet and promotes accretion (18 mm/year) causing the formation of over 108 ha of supratidal islands over the past 100 years. These newly formed islands are calculated to potentially contain over 5.5 million tonnes of CO2 equivalent carbon. Future management of the inlet and other Spartina‐dominated environments within Australian presents a dilemma for resource managers; on the one hand, Spartina is highly invasive and can outcompete native tidal marshes, thereby warranting its eradication, but on the other hand it is likely more resilient to rising sea levels and has the potential for carbon sequestration. Whether or not the potential advantages outweigh the significant habitat change that is anticipated, any management strategies will likely require additional research into costs and benefits of all ecosystem services provided by Spartina including in relation to nutrient cycling, shoreline stabilisation, and biodiversity as well as in response to the longevity of carbon found within the sediments.  相似文献   
2.
Two new species of benthic foraminifera have been identified from Holocene sediments of the Papuan Plateau. Spirorutilus collinsi sp. nov. (suborder Textulariina) has a rapidly tapering, agglutinated test with depressed sutures, flattened upper chamber surfaces, and a low, broad-arched aperture. The second species, Cibicorbis aspera sp. nov. (suborder Rotaliina), differs from others of the genus in having rugae on both sides of the test, as well as rugose to serrate dorsal sutures.  相似文献   
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Summary : The article explores deployment of the Darwinian narrative of the “natural history of humanity” in Russian physical anthropology in the late nineteenth to the early twentieth century. It traces two narratives developed by the leading Russian school of physical anthropology: one narrative advanced a universalist vision of collective scholarly enterprise working toward clarifying the missing links in the a priori accepted developmental evolutionary model. The other constructed a new language that undermined the idea of species/subspecies/races/nations/ as stable, externally bounded, and internally homogeneous units and attempted to rationalize imperial hybridity. The article's main focus is on the latter classificatory narrative, its relational methodology, and the protostructuralist units of comparison that it produced.  相似文献   
5.
Zoos and aquariums are responding to the worldwide biodiversity crisis through major conservation initiatives like captive breeding for assurance populations and reintroduction programs. These institutions also fundraise, offer education programs, and provide critical research on biodiversity. Through a case study inside three accredited Canadian zoos, this paper illustrates that zoos and their staff members are being incorporated into many official species‐at‐risk recovery efforts on provincial, federal, and international levels. Specifically, the zoos studied are involved in every stage of the recovery process, from providing valuable research and habitat analyses, to captive breeding animals for reintroduction, to writing recovery strategies and creating recovery policy for multiple jurisdictional levels. Zoo staff indicate that zoos are uniquely suited to conservation because zoos have space, expertise, apolitical status, and the ability to connect with the public. Overall, the paper suggests that zoos can significantly contribute to species‐at‐risk protection and recovery in Canada and beyond.  相似文献   
6.
The Early Cretaceous Otway and Strzelecki Groups exposed on the southern coast of Victoria, Australia, have produced a fauna of dinosaurs that lived within the Antarctic Circle. As many as five or six species of hypsilophodontids numerically dominate the collections from there, but the rarer and more fragmentary theropod remains suggest a surprising diversity of carnivorous dinosaurs. A possible surangular and an isolated vertebra have characters considered diagnostic for Late Cretaceous oviraptorosaurs of the Northern Hemisphere. Other fossils suggest the presence of ornithomimosaurs, dromaeosaurids and neoceratopsians, and with the possible oviraptorosaur remains, challenge the widespread assumption that these animals originated on the northern continents.  相似文献   
7.
Abstract

The collapse of empires is exceedingly difficult to understand. The author examined the distribution of imperial lifetimes using a data set that spans more than three millennia and found that it conforms to a memoryless exponential distribution in which the rate of collapse of an empire is independent of its age. Comparing this distribution to similar lifetime distributions of other complex systems—specifically, biological species and corporate firms—the author explores the reasons behind their lifetime distributions and how this approach can yield insights into empires.  相似文献   
8.
During the ten years covered by this review, the foci of studies in palaeobotany of plant megafossils and certain non-palynological plant microfossils included Precambrian palaeobotany, early vascular plants, Palaeozoic pteridosperms, conifers, and angiosperms. Botanically orientated investigations displayed an increasing use of the electron microscope. Interpretations of palaeoecology and reproductive biology of fossil plants gained increasing momentum. Biostratigraphic studies underwent some new activation but generally took second place to the amount of morphological work. The number of palaeobotanists who completed or received their training during the decade augurs well for the future; there is still much to be done.  相似文献   
9.
The modern history of collection and study of corals in the Permian strata of Timor began in 1911,with a German expedition (J.Wanner, leader) and a Dutch expedition (H. Molengraaff, leader) to collect Permian and Triassic fossils in the colony of Netherlands Timor, and with a survey by the Swiss geologist F. Weber the same year in Portuguese Timor, the eastern portion of the island. Later expeditions led by Jonker (1916) and Brouwer (1937), both of the Netherlands, greatly increased already huge collections of fossils and additionally, understanding of the island's geology. Monographic studies of these coral collections by Gerth (1921), Koker (1924), Schindewolf (1942), Hehenwarter (1951) and Schouppé & Stacul (1955, 1959) have much enhanced the systematic value of these fossil corals, both Rugosa and Tabulata. Locality information and maps containing collecting localities are somewhat scattered (Wanner 1931, Burck 1923, Marez Oyens 1940, Van Bemmelen 1949), but are summarized here. A list of all valid species names(109 Rugosa, 25 Tabulata) is appended to this paper, with type localities and horizon. Serious problems of nomenclature are avoided in this paper by accepting genus names used in Hill (1981), modified by later systematic studies, such as that of Fedorowski (1986), but some unknown number of names in the list of species are to be synonymized, especially since 31 of them are based on a single specimen (e.g. Niermann 1975). The biostratigraphy of these faunas is uncertain, in great part due to the greatest number of corals having been collected from a tectonic mélange sequence in the Baun to Basleo structural region, and additionally because of the purchase of huge numbers of fossils from the indigenous people of Timor, with accompanying uncertainties regarding locality and horizon data. The coral fauna of Permian age from Timor needs serious restudy to insure its stratigraphic and palaeontologic value, but future study will require new field collection of specimens from the relatively complete stratigraphic sequences in the northern ‘Fatu’ belt of outcrops. The huge numbers of individuals of some coral species provide great opportunities for understanding population structure in these faunas.  相似文献   
10.
Wyse Jackson, P.N., Reid, C.M. & McKinney, F.K., iFirst article, 2011. Fixation of the type species of the genus Protoretepora de Koninck, 1878 (Bryozoa, Fenestrata). Alcheringa, 1–2. ISSN 0311-5518.

The type species of the Palaeozoic bryozoan genus Protoretepora de Koninck, 1878 was originally fixed as Fenestella ampla Lonsdale in Darwin, 1844, but this taxon has been shown to belong to the bryozoan genus Parapolypora Morozova & Lisitsyn, 1996 Morozova, I. P. and Lisitsyn, D. V. 1996. Revision of the genus Polypora. Paleontologicheskii Zhurnal, 1996(4): 3847. [English translation: Paleontological Journal30(5), 530–541] [Google Scholar]. The original type species designation for Protoretepora de Koninck, 1878 is set aside, and in accordance with Article 70.3 of the International Code of Zoological Nomenclature (4th edition, 1999) the nominal species Protoretepora crockfordae Wyse Jackson, Reid & McKinney, 2011 from the Permian of Tasmania, Australia is herein fixed as the type species.  相似文献   
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