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111.
The distribution of the Karamoja Apalis Apalis karamojae, an East African endemic, has been sparsely documented in Uganda. In October 2011, a survey of the species was carried out near Iriiri in north-eastern Uganda. The main aim was to find out if there is a viable population of the species and to highlight the threats to its population. Sixteen 1-km transects in four sites were surveyed. The survey recorded nine individuals including a pair at an occupied nest, which is not conclusive for determining the viability of the population. The main threats to the species were cutting of the dominant shrub Vachellia drepanolobium (Acacia drepanolobium) in the area, farming and grazing. When we attempted luring the birds using the recorded song of the Karamoja Apalis from Tanzania, these individuals did not respond. We therefore recommend (1) to undertake a more detailed GIS survey to discover the extent of the suitable habitat, (2) to repeat the survey with improved effort to better estimate the viability of this population, (3) to conduct a study to ascertain the successful breeding of the species in the area, (4) to conduct a DNA analysis to compare the Iriiri population with the Tanzanian population, and (5) to record the song of the Ugandan birds for song analysis and to determine the response of Tanzanian birds.  相似文献   
112.
孙丹萍  刘玉卿  梁艺馨  杨建敏  姚孝宗 《动物学杂志》2016,51(3):383,448-383,448
正2013年7月9日,在河南省洛阳市栾川县老君山主峰西侧追梦谷(33°45′26″N,111°38′33″E,海拔830 m),进行蜻蜓多样性专项调查时,偶遇当地村民手中抓着两只漂亮的小鸟。经过仔细观察和辨认,鉴定为红胸啄花鸟(Dicaeum ignipectus),一雌一雄。我们将其带回"河南省林业厅林业有害生物防控重点实验室"精心喂养。两只红胸啄花鸟标本现保存于河南林业职业学院野生动物标本馆。经过查阅《中国鸟类分类与分布名录(第二版)》(郑光美2011)、《中国鸟类分布名录》(郑作新1976)、《中  相似文献   
113.
2010年7和8月,采用样带法于贵州省习水国家级自然保护区进行两栖动物资源调查,在三叉河片区(28°30′43.67″N,106°25′03.72″E,海拔1 087 m)采集到25只形态相似的两栖动物标本,经过鉴定,该标本为无尾目(Anura)叉舌蛙科(Dicroglossidae)棘胸蛙属(Quasipaa)的合江棘蛙(Q.robertingeri),系贵州省两栖动物新纪录。标本现保存于贵阳学院生态研究中心标本室。  相似文献   
114.
正2015年6月22日,在河北省平山县驼梁国家级自然保护区驼峰附近的华北落叶松林内(113°49′33″E,38°44′59″N,海拔2 056 m)观察到1雌1雄2只鹟科鸟类。雌鸟上体橄榄褐色,两翼各具1道棕白色的翼斑;喉部、胸部浅褐色,并略带皮黄;尾上覆羽沾棕色;眼周白色,嘴黑褐色。雄鸟上体暗蓝灰色,喉、上胸、两胁橙红色,腹部颜色逐渐变白,尾近黑色。发现时,雌鸟往返飞行于落叶松枝和地面进行觅食;雄鸟在落叶松上部的树枝上频繁地鸣唱。经查阅文献(约翰·马敬能等2000,曲利明2014,Clement et al.2016),确定该鸟种为锈胸蓝姬鹟(Ficedula hodgsonii)(图1)。  相似文献   
115.
Actinopterygii (ray‐finned fishes) and Elasmobranchii (sharks, skates and rays) represent more than half of today's vertebrate taxic diversity (approximately 33000 species) and form the largest component of vertebrate diversity in extant aquatic ecosystems. Yet, patterns of ‘fish’ evolutionary history remain insufficiently understood and previous studies generally treated each group independently mainly because of their contrasting fossil record composition and corresponding sampling strategies. Because direct reading of palaeodiversity curves is affected by several biases affecting the fossil record, analytical approaches are needed to correct for these biases. In this review, we propose a comprehensive analysis based on comparison of large data sets related to competing phylogenies (including all Recent and fossil taxa) and the fossil record for both groups during the Mesozoic–Cainozoic interval. This approach provides information on the ‘fish’ fossil record quality and on the corrected ‘fish’ deep‐time phylogenetic palaeodiversity signals, with special emphasis on diversification events. Because taxonomic information is preserved after analytical treatment, identified palaeodiversity events are considered both quantitatively and qualitatively and put within corresponding palaeoenvironmental and biological settings. Results indicate a better fossil record quality for elasmobranchs due to their microfossil‐like fossil distribution and their very low diversity in freshwater systems, whereas freshwater actinopterygians are diverse in this realm with lower preservation potential. Several important diversification events are identified at familial and generic levels for elasmobranchs, and marine and freshwater actinopterygians, namely in the Early–Middle Jurassic (elasmobranchs), Late Jurassic (actinopterygians), Early Cretaceous (elasmobranchs, freshwater actinopterygians), Cenomanian (all groups) and the Paleocene–Eocene interval (all groups), the latter two representing the two most exceptional radiations among vertebrates. For each of these events along with the Cretaceous‐Paleogene extinction, we provide an in‐depth review of the taxa involved and factors that may have influenced the diversity patterns observed. Among these, palaeotemperatures, sea‐levels, ocean circulation and productivity as well as continent fragmentation and environment heterogeneity (reef environments) are parameters that largely impacted on ‘fish’ evolutionary history, along with other biotic constraints.  相似文献   
116.
117.
正相对于西方而言,古北区的东侧,轮虫的研究资料非常缺乏~([3])。中国现存的很多轮虫资料也已经非常陈旧~([4—6]),当然,近年也有一些论文相继报道了这一淡水系统中非常重要的浮游动物类群~([7—12]),其中不乏涉及分子方法研究轮虫分类~([13])和轮虫的生态研究~([14])。但是从已有的资料可以发现,很多已知的轮虫分布大多集中在武汉、海南、洞庭湖、西藏等地,我们可以看到一个很显然的现象,即只有中国的这些地方被较为详细地研究过,  相似文献   
118.
报道了四川重楼属植物2新分布变种,分别是宽瓣球药隔重楼(Paris fargesii var. latipetala H. Li et V. G. Soukup)和红果五指莲(Paris axialis H. Li var. rubra H. H. Zhou, K. Y. Wu et R. Tao)。其中红果五指莲为贵州特有类群,且为孤点分布。四川新分布的发现对于重楼属植物的系统分类和迁徙演化研究具有重要意义。  相似文献   
119.
报道了酢浆草科(Oxalidaceae)感应草属(Biophytum DC.)的1个中国新记录种——长梗感应草[Biophytum reinwardtii(Zucc.)Klotzsch],提供了其形态描述和标本照片,并对其后选模式作了选定。该种新发现于中国西南部中缅边境的盈江县。长梗感应草与感应草[B.sensitivum(Linn.)Candolle]最为近似,但前者的花梗在花期长5~7mm,而后者的花梗长约1mm,两者容易区别。  相似文献   
120.
The fossil record provides direct empirical data for understanding macroevolutionary patterns and processes. Inherent biases in the fossil record are well known to confound analyses of this data. Sampling bias proxies have been used as covariates in regression models to test for such biases. Proxies, such as formation count, are associated with paleobiodiversity, but are insufficient for explaining species dispersal owing to a lack of geographic context. Here, we develop a sampling bias proxy that incorporates geographic information and test it with a case study on early tetrapodomorph biogeography. We use recently-developed Bayesian phylogeographic models and a new supertree of early tetrapodomorphs to estimate dispersal rates and ancestral habitat locations. We find strong evidence that geographic sampling bias explains supposed radiations in dispersal rate (potential adaptive radiations). Our study highlights the necessity of accounting for geographic sampling bias in macroevolutionary and phylogenetic analyses and provides an approach to test for its effect.  相似文献   
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