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91.
The recognition of broad biogeographic provinces provides an important framework for ecological and conservation biological research. Marine biologists have long recognized distinct biogeographic provinces in southern Australia, primarily on the basis of qualitative differences in intertidal species assemblages. Here we provide an a priori test for these traditional eastern (Peronian), western (Flindersian) and south‐eastern (Maugean) provinces. Specifically, we analyse distributional data for approximately 1500 algal species using the newly available Australian Virtual Herbarium, an online database of herbarium specimens. Our quantitative algal analyses across southern Australia identify three distinct biogeographic assemblages, consistent with traditional qualitative provinces. We argue that these broad provinces provide a highly effective framework for understanding and managing Australia's marine biodiversity. In particular, biogeographic provinces provide a regional framework for integrating the ongoing discovery of biological variation at finer scales. More broadly therefore we recommend that biologists undertake quantitative analyses to test provincial biogeographic boundaries around the globe.  相似文献   
92.
以广东中山树木园20种含笑属植物为对象,研究其引种后的生长表现。结果表明:20种含笑属植物在中山树木园均生长良好,分析的13种含笑属植物在胸径、树高及冠幅的生长量上均存在显著差异。本地苗木黄兰、白兰、乐昌含笑及火力楠在树高、胸径及冠幅方面表现优异。2004年于湖南引种的5种含笑以灰绒含笑和多花含笑生长最好;2005至2009年引种的7种含笑属植物以亮叶含笑表现最佳。  相似文献   
93.
在福建省药用植物资源调查中,陆续发现了福建省被子植物地理分布新记录属及种多个,经整理鉴定,本文继续报道了1个分布新记录科霉草科(Triuridaceae),2个分布新记录属喜荫草属(Sciaphila)和红葱属(Eleutherine),以及败酱叶菊芹 Erechtites valerianaefolia、大柱霉草 Sciaphila secundiflora、红葱 Eleutherine plicata和纤草Burmannia itoana等4个分布新记录种。标本存放于福建中医药大学药用植物标本室(FJTCM)。  相似文献   
94.
The vascular flora of the Siahrud e Rudbar protected area was investigated in the years 2007 and 2008. It is a sylvatic area in the Guilan province with a total area of approximately 28289 hectares. A total of 711 plant specimens were collected and 616 species, subspecies, and varieties, belonging to 373 genera and 101 families were identified. Of these, 14 species (23%) are endemic to Iran. The documented flora exhibited many typically Hyrcanian species, including Hyrcanian endemics. The global phytogeographical affinities of the species were as follows: Euro Siberian 212%, Iran Turanian & Euro Siberian 168%, Pluriregional 117%, Iran Turanian 106%, and Cosmopolite 55%.  相似文献   
95.
An ethnobotanical survey on the medicinal plant species marketed in Quanzhou, southern Fujian, was conducted in order to document traditional medicinal knowledge and application of medicinal plants in dietary. In addition to literature review, data was obtained using ethnobotanical tools and methods, including personal interviews during field trips, collecting herbarium specimens, and species identification by cross referencing. The results showed that: 1) There are 148 wild medicinal species, belonging to 56 plant families and 117 genera present in Quanzhou, southern Fujian. Among them, 46 species are edible wild herbs, 37 species are medicinal plants, 38 species are used as tea substituting plants or herbal tea,22 species are wild fruits, 4 species are used as spices and 1 species is used to make bean jelly; 2) The plant families which comprise a major part of the pool are Compositae, Lamiaceae, Rosaceae, Leguminosae, Rubiaceae, Liliaceae, Orchidaceae and Moraceae; 3) This study explored the utilization of the medicinal plants in Quanzhou area, and proposed methods to inherit the culture of using wild plants in dietary, as well as methods to conserve the edible medicinal wild plant resources.  相似文献   
96.
城隍竹——福建竹亚科一新种   总被引:1,自引:0,他引:1  
报道了竹亚科(Bambusoideae)少穗竹属(Oligostachyum Z.P.Wang et G.H.Ye)一新种——城隍竹(O. heterophyllum M.M.Lin)。该新种分布于我国福建西部,它与糙花少穗竹[O.scabriflorum(McClure) Z.P.Wang et G.H.Ye]相似或近缘,但秆小,直径不超过1.5 cm;秆箨淡紫绿色,背面具有瘤基刺毛,无斑点,无白粉,亦无焦边,基部密被细刚毛;箨片直立,基部不收缩;箨舌淡禾秆色;叶鞘被细微柔毛而与后者相区别。  相似文献   
97.
98.
In this study, we use tree‐ring records to determine the climate factors controlling the growth of Centrolobium microchaete, a high‐value timber species from the tropical dry Chiquitano forest in Bolivia. We present the first tree‐ring chronologies from C. microchaete for Concepción and Santa Mónica, Bolivia. Statistical analyses show that the chronologies are of good quality and have a significant common signal between trees. The growth of C. microchaete is strongly influenced by climatic conditions during late spring–early summer. Abundant precipitations concurrent with below‐average temperatures during this period of the year favor tree growth. Climate variations in late spring–early summer explain >40 percent of the total variance in C. microchaete tree growth during the interval 1943–2005. Minor differences in tree responses to climate recorded between the two stands may reflect differences in the extent of the dry season and in soil water capacity between sites. Although the chronologies cover the past 180 yr, adding samples from older individuals would permit the extension of these records further back in time. The strong climate dependency of tree growth suggests that predicted future climate changes in the region could have a significant influence on C. microchaete tree growth during the 21st century.  相似文献   
99.
Macaronesia is a biogeographical region comprising five Atlantic Oceanic archipelagos: the Azores, Madeira, Selvagen (Savage Islands), Canaries and Cape Verde. It has strong affinities with the Atlantic coast of the Iberian Peninsula and the north‐western fringes of Africa. This paper re‐evaluates the biogeographical history and relationships of Macaronesia in the light of geological evidence, which suggests that large and high islands may have been continuously available in the region for very much longer than is indicated by the maximum surface area of the oldest current island (27 Ma) – possibly for as long as 60 million years. We review this literature, attempting a sequential reconstruction of Palaeo‐Macaronesia from 60 Ma to the present. We consider the implications of these geological dynamics for our understanding of the history of colonization of the present islands of Macaronesia. We also evaluate the role of these archipelagos as stepping stones and as both repositories of palaeo‐endemic forms and crucibles of neo‐endemic radiations of plant and animal groups. Our principal focus is on the laurel forest communities, long considered impoverished relicts of the Palaeotropical Tethyan flora. This account is therefore contextualized by reference to the long‐term climatic and biogeographical history of Southern Europe and North Africa and by consideration of the implications of changes in land–sea configuration, climate and ocean circulation for Macaronesian biogeography. We go on to provide a synthesis of the more recent history of Macaronesian forests, which has involved a process of impoverishment of the native elements of the biota that has accelerated since human conquest of the islands. We comment briefly on these processes and on the contemporary status and varied conservation opportunities and threats facing these forests across the Macaronesian biogeographical region.  相似文献   
100.
对台湾海峡西北部平潭岛海域337个站位表层沉积物中底栖有孔虫进行分析鉴定,结果表明底栖有孔虫丰度、分异度变化较大,所出现的属种类型以玻璃质壳体为主,其次为瓷质壳,胶结壳最少。底栖有孔虫分布受水深、盐度、底质类型、底流和沿岸上升流等因素共同影响。应用‘PAST’软件的因子分析结果表明,该海域底栖有孔虫可划分为四个组合:组合Ⅰ(Hanzawaia-Pseudorotalia-Bolivina)主要分布于水深大于20m的深水区,受水深和底流影响明显;组合Ⅱ(Ammonia beccarii-Elphidiumspp.)主要分布于近岸浅水环境;组合Ⅲ(Quinqueloculina-Ammonia annectens-Spiroloculina)主要分布于海湾内高盐度区,推测受到沿岸上升流影响;组合Ⅳ(Elphidium advenum-Ammonia annectens)分布于组合Ⅰ与组合Ⅲ之间的局部区域,可能受浙闽沿岸流影响较强。  相似文献   
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