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991.
A new species Scelidopetalon biwenxuani sp. n. is described from China, representing the first occurrence of the genus in Hainan province. A key to the world species of this genus is provided.  相似文献   
992.
Widespread fish clades that occur mainly or exclusively in fresh water represent a key target of biogeographical investigation due to limited potential for crossing marine barriers. Timescales for the origin and diversification of these groups are crucial tests of vicariant scenarios in which continental break‐ups shaped modern geographic distributions. Evolutionary chronologies are commonly estimated through node‐based palaeontological calibration of molecular phylogenies, but this approach ignores most of the temporal information encoded in the known fossil record of a given taxon. Here, we review the fossil record of freshwater fish clades with a distribution encompassing disjunct landmasses in the southern hemisphere. Palaeontologically derived temporal and geographic data were used to infer the plausible biogeographic processes that shaped the distribution of these clades. For seven extant clades with a relatively well‐known fossil record, we used the stratigraphic distribution of their fossils to estimate confidence intervals on their times of origin. To do this, we employed a Bayesian framework that considers non‐uniform preservation potential of freshwater fish fossils through time, as well as uncertainty in the absolute age of fossil horizons. We provide the following estimates for the origin times of these clades: Lepidosireniformes [125–95 million years ago (Ma)]; total‐group Osteoglossomorpha (207–167 Ma); Characiformes (120–95 Ma; a younger estimate of 97–75 Ma when controversial Cenomanian fossils are excluded); Galaxiidae (235–21 Ma); Cyprinodontiformes (80–67 Ma); Channidae (79–43 Ma); Percichthyidae (127–69 Ma). These dates are mostly congruent with published molecular timetree estimates, despite the use of semi‐independent data. Our reassessment of the biogeographic history of southern hemisphere freshwater fishes shows that long‐distance dispersals and regional extinctions can confound and erode pre‐existing vicariance‐driven patterns. It is probable that disjunct distributions in many extant groups result from complex biogeographic processes that took place during the Late Cretaceous and Cenozoic. Although long‐distance dispersals likely shaped the distributions of several freshwater fish clades, their exact mechanisms and their impact on broader macroevolutionary and ecological dynamics are still unclear and require further investigation.  相似文献   
993.
《环境昆虫学报》2014,(5):826-827
本文首次报道了采于中国海南一新记录种白横迷钩蛾Microblepsis cupreogrisea (Hampson, 1895)。该种隶属于钩蛾科Drepanidae迷钩蛾属Microblepsis Warren, 1922,对成虫外部形态和外生殖器特征进行了简要描述,并提供其图片。研究标本保存于华南农业大学资源环境学院昆虫学系。  相似文献   
994.
The presence of Couch's goby in the Mediterranean Sea   总被引:2,自引:0,他引:2  
Known distribution of Couch's goby, Gobius couchi Miller & El-Tawil, 1974 formerly limited to the British Isles, appears now to be extended to the Mediterranean. A new specimen collected at the island of Ischia, near Naples, Italy, is described.  相似文献   
995.
One specimen of Almaco jack Seriola rivoliana is recorded for the first time in the Mediterranean Sea. It was caught in a purse seine off Lampedusa Island in June 2000 and is listed as a new alien fish from the Atlantic Ocean.  相似文献   
996.
西藏南部地形较为复杂,植物资源丰富,物种多样性高。笔者在对西藏山南地区高山植物多样性调查过程中,经野外调查、采集标本、查阅植物志等相关资料及分类鉴定,结果发现,山南地区隆子县的无心菜属(Arenaria)球花福禄草[A. globiflora (Fenzl) Edgew. & Hook. f.]和错那县蝇子草属(Silene)的错那蝇子草(S. birgittae Bocquet)为中国新记录种。该报道一方面丰富了中国植物区系的内容,更新了国产石竹科植物资料,对中国西藏山南地区植物多样性的保护及研究具有一定意义。另一方面说明中国西藏山南地区的植物多样性调查仍存在许多调查薄弱地区,还需加强相关地区植物多样性调查工作。  相似文献   
997.
The subtidal brown algal species Sporochnus dotyi Brostoff (Sporochnales, Phaeophyceae), which has been regarded as a Hawaiian endemic, is reported from Kushimoto, Kii Peninsula, Pacific coast of central Honshu, Japan, for the first time outside Hawai'i. The species grew on subtidal rocks ca. 5–20 m deep attached by a small conical holdfast. The erect thalli were 5–30 cm high, terete, robust and alternately branched in 1–2 orders. When mature, pedicellate receptacles developed on the branches, and formed elliptical sori 1 mm long with a pedicel 3–5 mm long. The apical parts of the thalli and the receptacles were terminated with a tuft of simple assimilatory filaments of up to 4 mm long and showed prominent green to yellow underwater iridescence. Reproductive filaments (paraphyses) were densely packed, simple, up to 200 μm long and bore 4–6 mostly unilateral unilocular zoidangia 20–22 μm long and 5–6 m in diameter. In the genetic analyses, the Sporochnus alga from Kushimoto had partial rbcL sequence identical to S. dotyi from Hawai'i. The cox3 phylogeny revealed that this alga formed a fully supported clade with S. dotyi. Therefore, we identified the alga from Kushimoto as S. dotyi. This finding of S. dotyi from Japan, together with the recent reports of the mesophotic macroalgae Ryuguphycus kuaweuweu (=Umbraulva kuaweuweu), Ulva iliohaha and Newhousia imbricata from various localities in the Pacific Ocean including Japan, suggest closer biogeographical connections of subtidal/mesophotic macroalgae in the Pacific than previously recognized.  相似文献   
998.

Aims

Spatio-temporal processes play a key role in ecology, from genes to large-scale macroecological and biogeographical processes. Existing methods studying such spatio-temporally structured data either simplify the dynamic structure or the complex interactions of ecological drivers. The aim of this paper is to present a generic method for ecological research that allows analysing spatio-temporal patterns of biological processes at large spatial scales by including the time-varying variables that drive these dynamics.

Location

Global analysis at the level of 272 regions.

Methods

We introduce a method called relational event modelling (REM). REM relies on temporal interaction dynamics that encode sequences of relational events connecting a sender node to a recipient node at a specific point in time. We apply REM to the spread of alien species around the globe between 1880 and 2005, following accidental or deliberate introductions into geographical regions outside of their native range. In this context, a relational event represents the new occurrence of an alien species given its former distribution.

Results

The application of relational event models to the first reported invasions of 4835 established alien species outside of their native ranges from four major taxonomic groups enables us to unravel the main drivers of the dynamics of the spread of invasive alien species. Combining the alien species first records data with other spatio-temporal information enables us to discover which factors have been responsible for the spread of species across the globe. Besides the usual drivers of species invasions, such as trade, land use and climatic conditions, we also find evidence for species-interconnectedness in alien species spread.

Conclusions

Relational event models offer the capacity to account for the temporal sequences of ecological events such as biological invasions and to investigate how relationships between these events and potential drivers change over time.  相似文献   
999.
《Palaeoworld》2023,32(1):124-135
Four new laniatorean harvestmen specimens (Arachnida: Opiliones: Laniatores) are described from the mid-Cretaceous (upper Albian–lower Cenomanian) Burmese amber of Northern Myanmar. One is placed as Insidiatores indet., but is not formally named as it is probably immature. Burmalomanius circularis n. gen. n. sp. and Petroburma tarsomeria n. gen. n. sp. represent the first fossil records of the extant families Podoctidae and Petrobunidae respectively. Finally, Mesodibunus tourinhoae n. gen. n. sp. belongs to Epedanidae, a family previously recorded from Burmese amber. These new records bring the total number of Burmese amber laniatorean species to ten, and the total number of fossil laniatoreans to fifteen. The new finds offer additional calibration points for the Laniatores tree of life and are consistent with the hypothesis that the modern Laniatores fauna of Southeast Asia may have had Gondwanan, as opposed to a Laurasian, origins.  相似文献   
1000.
2021年9月13日在浙江德清莫干山(30°36′27″N,119°51′39″E,海拔601 m)采集到1只刺猬标本。该标本耳较短,不超过周围棘刺长。体背棘刺短细,几无全白色棘刺,大部分棘刺从基部至刺尖分为4段:第1段白色,长度占棘刺长2/3以上;第2段黑色或深褐色,约3~5 mm;第3段白色,约1~3 mm;第4段,即棘刺尖端,黑色或深褐色。头骨吻部较短,鼻骨狭长;整个额部较为平直;矢状脊不发达,但明显可见;人字脊发达。这些特征与侯氏猬(Mesechinushughi)的鉴别特征基本一致。基于Cytb全序列构建的最大似然树显示,该标本与安徽的侯氏猬聚为一支(支持率100%),该支又与陕西的侯氏猬聚为一支(支持率97%),并构成单系群。该标本Cytb全序列与安徽的侯氏猬遗传距离为0.35%,与陕西的侯氏猬遗传距离为4.92%~5.27%。基于以上结果,确定该标本为侯氏猬。这是林猬属侯氏猬在浙江省的首次记录,也是继安徽发现侯氏猬以来,再次在长江以南发现侯氏猬的新分布点。根据已获取的信息,浙江的侯氏猬在浙西丘陵山区分布较广,主要栖息在林地生境,与东北刺猬(Erinaceus amuren...  相似文献   
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